Assignment 5: Hash Table implementation and concordance There are three parts to this assignment. In the first two parts, you will complete the implementation of a hash map and a concordance program. In the third part, you will answer a number of questions using the concordance program. There is also an extra credit opportunity.

Prerequisites Reading chapter 12, watching this weeks lecture on hash tables with chaining, and completing worksheet 38 will better prepare you to tackle this assignment. It may also be helpful to review C file I/O with fopen() and fclose().

Hash map First complete the hash map implementation in hashMap.c. This hash map uses a table of buckets, each containing a linked list of hash links. Each hash link stores the key-value pair (string and integer in this case) and a pointer to the next link in the list. See hashMap.h and the accompanied drawing posted with this assignment for clarification. You must implement each function in hashMap.c with the // FIXME: implement comment. At the top of hashMap.h you should see two macros: HASH_FUNCTION and MAX_TABLE_LOAD. You are free to change their definitions but know that the default values will be used when grading. HASH_FUNCTION is the name of the hash function you want to use. You will change this when answering the written part of the assignment. Make sure everywhere in your implementation to use HASH_FUNCTION(key) instead of directly calling a hash function. MAX_TABLE_LOAD is the table load threshold on which you should resize the table.

A number of tests for the hash map are included in tests.c. Each one of these test cases use several or all of the hash map functions, so dont expect tests to pass until you implement all of them. Each test case is slightly more thorough than the one before it and there is a lot of redundancy to better ensure correctness. Use these tests to help you debug your hash map implementation. They will also help your TA grade your submission. You can build the tests with make tests or make and run them with ./tests.

Concordance The concordance counts how many times each word occurs in a document. You will implement a concordance using the hash map implementation from the previous part. Each hash link in the table will store a word from the document as the key and the number of times the word appeared as the value. You must finish the concordance implementation in main.c. You are provided with a function nextWord() which takes a FILE*, allocates memory for the next word in the file, and returns the word. If the end of the file is reached, nextWord() will return NULL. It is your job to open the file using fopen(), populate the concordance with the words, and close the file with fclose(). The file name to open should be given as a command line argument when running the program. It will default to input1.txt if no file name is provided. Your concordance code should loop over the words until the end of the file is reached, doing the following steps each iteration: 1. Get the next word with getWord. 2. If the word is already in the hash map, then increment its number of occurrences. 3. Otherwise, put the word in the hash map with a count of 1. 4. Free the word.

After processing the text file, print all words and occurrence counts in the hash map. Please print them in the format of the following example above the call to hashMapPrint(): best: 1 It: 2 was: 2 the: 2 of: 2 worst: 1 times: 2 You can build the program with make prog or make and run it with ./prog , where is the name of a text file like input1.txt.

Written Submit a pdf or text file answering the following questions: 1. Give an example of two words that would hash to the same value using hashFunction1 but would not using hashFunction2. 2. Why does the above observation make hashFunction2 superior to hashFunction1? 3. When you run your program on the same input file once with hashFunction1 and once with hashFunction2, is it possible for your hashMapSize function to return different values? 4. When you run your program on the same input file once with hashFunction1 and once with hashFunction2, is it possible for your hashMapTableLoad function to return different values? 5. When you run your program on the same input file once with hashFunction1 and once with hashFunction2, is it possible for your hashMapEmptyBuckets function to return different values? 6. Is there any difference in the number of empty buckets when you change the table size from an even number like 1000 to a prime like 997? Extra credit There are a lot of uses for a hash map, and one of them is implementing a spell checker. All you need to get started is a dictionary, which is provided in dictionary.txt. In spellChecker.c you will find some code to get you started with the spell checker. It is fairly similar to the code in main.c. You can build the program with make spellChecker. FYI: The spellchecker program flow should as following - 1. The user types in a word 2. Potential matches are outputted Like "Did you mean...?" etc 3. Continue to prompt user for word until they type quit

The best way to implement a dictionary that's used for a spellchecker would probably be to design it with that purpose in mind from the beginning, i.e. associating a similarity for each word to some base word (maybe "abcdefghijklmnopqrstuvwyz") and then incorporating that into the hash function. There are better ways ( https://en.wikipedia.org/wiki/Levenshtein_distance) to establish similarity than computing the cosine of the angle between two vectors (strings) to create a list of candidates and further winnowed that list according to substring comparisons. So, I would say calculating the Levenshtein distance between the misspelled word and all strings in the dictionary, create 5/6 best candidates and print them as suggestion. Files are below, must be written in C.

CuTest.h

#ifndef CU_TEST_H #define CU_TEST_H

#include #include

#define CUTEST_VERSION "CuTest 1.5"

/* CuString */

char* CuStrAlloc(int size); char* CuStrCopy(const char* old);

#define CU_ALLOC(TYPE) ((TYPE*) malloc(sizeof(TYPE)))

#define HUGE_STRING_LEN 8192 #define STRING_MAX 256 #define STRING_INC 256

typedef struct { int length; int size; char* buffer; } CuString;

void CuStringInit(CuString* str); CuString* CuStringNew(void); void CuStringRead(CuString* str, const char* path); void CuStringAppend(CuString* str, const char* text); void CuStringAppendChar(CuString* str, char ch); void CuStringAppendFormat(CuString* str, const char* format, ...); void CuStringInsert(CuString* str, const char* text, int pos); void CuStringResize(CuString* str, int newSize); void CuStringDelete(CuString* str);

/* CuTest */

typedef struct CuTest CuTest;

typedef void (*TestFunction)(CuTest *);

struct CuTest { char* name; TestFunction function; int failed; int ran; int parents; char* message; jmp_buf *jumpBuf; };

void CuTestInit(CuTest* t, const char* name, TestFunction function); CuTest* CuTestNew(const char* name, TestFunction function); CuTest* CuTestCopy(CuTest* t); void CuTestRun(CuTest* tc); void CuTestDelete(CuTest *t);

/* Internal versions of assert functions -- use the public versions */ void CuFail_Line(CuTest* tc, const char* file, int line, const char* message2, const char* message); void CuAssert_Line(CuTest* tc, const char* file, int line, const char* message, int condition); void CuAssertStrEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, const char* expected, const char* actual); void CuAssertIntEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, int expected, int actual); void CuAssertDblEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, double expected, double actual, double delta); void CuAssertPtrEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, void* expected, void* actual);

/* public assert functions */

#define CuFail(tc, ms) CuFail_Line( (tc), __FILE__, __LINE__, NULL, (ms)) #define CuAssert(tc, ms, cond) CuAssert_Line((tc), __FILE__, __LINE__, (ms), (cond)) #define CuAssertTrue(tc, cond) CuAssert_Line((tc), __FILE__, __LINE__, "assert failed", (cond))

#define CuAssertStrEquals(tc,ex,ac) CuAssertStrEquals_LineMsg((tc),__FILE__,__LINE__,NULL,(ex),(ac)) #define CuAssertStrEquals_Msg(tc,ms,ex,ac) CuAssertStrEquals_LineMsg((tc),__FILE__,__LINE__,(ms),(ex),(ac)) #define CuAssertIntEquals(tc,ex,ac) CuAssertIntEquals_LineMsg((tc),__FILE__,__LINE__,NULL,(ex),(ac)) #define CuAssertIntEquals_Msg(tc,ms,ex,ac) CuAssertIntEquals_LineMsg((tc),__FILE__,__LINE__,(ms),(ex),(ac)) #define CuAssertDblEquals(tc,ex,ac,dl) CuAssertDblEquals_LineMsg((tc),__FILE__,__LINE__,NULL,(ex),(ac),(dl)) #define CuAssertDblEquals_Msg(tc,ms,ex,ac,dl) CuAssertDblEquals_LineMsg((tc),__FILE__,__LINE__,(ms),(ex),(ac),(dl)) #define CuAssertPtrEquals(tc,ex,ac) CuAssertPtrEquals_LineMsg((tc),__FILE__,__LINE__,NULL,(ex),(ac)) #define CuAssertPtrEquals_Msg(tc,ms,ex,ac) CuAssertPtrEquals_LineMsg((tc),__FILE__,__LINE__,(ms),(ex),(ac))

#define CuAssertPtrNotNull(tc,p) CuAssert_Line((tc),__FILE__,__LINE__,"null pointer unexpected",(p != NULL)) #define CuAssertPtrNotNullMsg(tc,msg,p) CuAssert_Line((tc),__FILE__,__LINE__,(msg),(p != NULL))

/* CuSuite */

#define MAX_TEST_CASES 1024

#define SUITE_ADD_TEST(SUITE,TEST) CuSuiteAdd(SUITE, CuTestNew(#TEST, TEST))

typedef struct { int count; CuTest* list[MAX_TEST_CASES]; int failCount;

} CuSuite;

void CuSuiteInit(CuSuite* testSuite); CuSuite* CuSuiteNew(void); void CuSuiteDelete(CuSuite *testSuite); void CuSuiteAdd(CuSuite* testSuite, CuTest *testCase); void CuSuiteAddSuite(CuSuite* testSuite, CuSuite* testSuite2); void CuSuiteConsume(CuSuite* testSuite, CuSuite* testSuite2); void CuSuiteRun(CuSuite* testSuite); void CuSuiteSummary(CuSuite* testSuite, CuString* summary); void CuSuiteDetails(CuSuite* testSuite, CuString* details);

#endif /* CU_TEST_H */

CuTest.c

#include #include #include #include #include #include #include

#include "CuTest.h"

char* CuStrAlloc(int size) { char* newStr = (char*) malloc( sizeof(char) * (size) ); return newStr; }

char* CuStrCopy(const char* old) { int len = strlen(old); char* newStr = CuStrAlloc(len + 1); strcpy(newStr, old); return newStr; }

void CuStringInit(CuString* str) { str->length = 0; str->size = STRING_MAX; str->buffer = (char*) malloc(sizeof(char) * str->size); str->buffer[0] = '\0'; }

CuString* CuStringNew(void) { CuString* str = (CuString*) malloc(sizeof(CuString)); str->length = 0; str->size = STRING_MAX; str->buffer = (char*) malloc(sizeof(char) * str->size); str->buffer[0] = '\0'; return str; }

void CuStringDelete(CuString *str) { if (!str) return; free(str->buffer); free(str); }

void CuStringResize(CuString* str, int newSize) { str->buffer = (char*) realloc(str->buffer, sizeof(char) * newSize); str->size = newSize; }

void CuStringAppend(CuString* str, const char* text) { int length;

if (text == NULL) { text = "NULL"; }

length = strlen(text); if (str->length + length + 1 >= str->size) CuStringResize(str, str->length + length + 1 + STRING_INC); str->length += length; strcat(str->buffer, text); }

void CuStringAppendChar(CuString* str, char ch) { char text[2]; text[0] = ch; text[1] = '\0'; CuStringAppend(str, text); }

void CuStringAppendFormat(CuString* str, const char* format, ...) { va_list argp; char buf[HUGE_STRING_LEN]; va_start(argp, format); vsprintf(buf, format, argp); va_end(argp); CuStringAppend(str, buf); }

void CuStringInsert(CuString* str, const char* text, int pos) { int length = strlen(text); if (pos > str->length) pos = str->length; if (str->length + length + 1 >= str->size) CuStringResize(str, str->length + length + 1 + STRING_INC); memmove(str->buffer + pos + length, str->buffer + pos, (str->length - pos) + 1); str->length += length; memcpy(str->buffer + pos, text, length); }

void CuTestInit(CuTest* t, const char* name, TestFunction function) { t->name = CuStrCopy(name); t->failed = 0; t->ran = 0; t->parents = 0; t->message = NULL; t->function = function; t->jumpBuf = NULL; }

CuTest* CuTestNew(const char* name, TestFunction function) { CuTest* tc = CU_ALLOC(CuTest); CuTestInit(tc, name, function); return tc; }

CuTest* CuTestCopy(CuTest* t) { CuTest* copy = CU_ALLOC(CuTest); memcpy(copy, t, sizeof(CuTest)); return copy; }

void CuTestDelete(CuTest *t) { if (!t) return; if (--t->parents < 1) { free(t->name); free(t->message); free(t); } }

void CuTestRun(CuTest* tc) { jmp_buf buf; tc->jumpBuf = &buf; if (setjmp(buf) == 0){ tc->ran = 1; (tc->function)(tc); } tc->jumpBuf = 0; }

static void CuFailInternal(CuTest* tc, const char* file, int line, CuString* string) { char buf[HUGE_STRING_LEN];

sprintf(buf, "%s:%d: ", file, line); CuStringInsert(string, buf, 0);

tc->failed = 1; tc->message = string->buffer; if (tc->jumpBuf != 0) longjmp(*(tc->jumpBuf), 0); }

void CuFail_Line(CuTest* tc, const char* file, int line, const char* message2, const char* message) { CuString string;

CuStringInit(&string); if (message2 != NULL){ CuStringAppend(&string, message2); CuStringAppend(&string, ": "); } CuStringAppend(&string, message); CuFailInternal(tc, file, line, &string); }

void CuAssert_Line(CuTest* tc, const char* file, int line, const char* message, int condition) { if (condition) return; CuFail_Line(tc, file, line, NULL, message); }

void CuAssertStrEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, const char* expected, const char* actual) { CuString string; if ((expected == NULL && actual == NULL) || (expected != NULL && actual != NULL && strcmp(expected, actual) == 0)) { return; }

CuStringInit(&string); if (message != NULL){ CuStringAppend(&string, message); CuStringAppend(&string, ": "); } CuStringAppend(&string, "expected <"); CuStringAppend(&string, expected); CuStringAppend(&string, "> but was <"); CuStringAppend(&string, actual); CuStringAppend(&string, ">"); CuFailInternal(tc, file, line, &string); }

void CuAssertIntEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, int expected, int actual) { char buf[STRING_MAX]; if (expected == actual) return; sprintf(buf, "expected <%d> but was <%d>", expected, actual); CuFail_Line(tc, file, line, message, buf); }

void CuAssertDblEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, double expected, double actual, double delta) { char buf[STRING_MAX]; if (fabs(expected - actual) <= delta) return; sprintf(buf, "expected <%f> but was <%f>", expected, actual);

CuFail_Line(tc, file, line, message, buf); }

void CuAssertPtrEquals_LineMsg(CuTest* tc, const char* file, int line, const char* message, void* expected, void* actual) { char buf[STRING_MAX]; if (expected == actual) return; sprintf(buf, "expected pointer <0x%p> but was <0x%p>", expected, actual); CuFail_Line(tc, file, line, message, buf); }

void CuSuiteInit(CuSuite* testSuite) { testSuite->count = 0; testSuite->failCount = 0; memset(testSuite->list, 0, sizeof(testSuite->list)); }

CuSuite* CuSuiteNew(void) { CuSuite* testSuite = CU_ALLOC(CuSuite); CuSuiteInit(testSuite); return testSuite; }

void CuSuiteDelete(CuSuite *testSuite) { unsigned int n; for (n=0; n < MAX_TEST_CASES; n++){ if (testSuite->list[n]){ CuTestDelete(testSuite->list[n]); } } free(testSuite);

}

void CuSuiteAdd(CuSuite* testSuite, CuTest *testCase) { assert(testSuite->count < MAX_TEST_CASES); testSuite->list[testSuite->count] = testCase; testSuite->count++; if (testCase->parents != INT_MAX){ testCase->parents++; } else{ testCase = CuTestCopy(testCase); } }

void CuSuiteAddSuite(CuSuite* testSuite, CuSuite* testSuite2) { int i; for (i = 0 ; i < testSuite2->count ; ++i){ CuTest* testCase = testSuite2->list[i]; CuSuiteAdd(testSuite, testCase); } }

void CuSuiteConsume(CuSuite* testSuite, CuSuite* testSuite2) { CuSuiteAddSuite(testSuite, testSuite2); CuSuiteDelete(testSuite2); }

void CuSuiteRun(CuSuite* testSuite) { int i; for (i = 0 ; i < testSuite->count ; ++i){ CuTest* testCase = testSuite->list[i]; CuTestRun(testCase); if (testCase->failed) { testSuite->failCount += 1; } } }

void CuSuiteSummary(CuSuite* testSuite, CuString* summary) { int i; for (i = 0 ; i < testSuite->count ; ++i){ CuTest* testCase = testSuite->list[i]; CuStringAppend(summary, testCase->failed ? "F" : "."); } CuStringAppend(summary, " "); }

void CuSuiteDetails(CuSuite* testSuite, CuString* details) { int i; int failCount = 0;

if (testSuite->failCount == 0){ int passCount = testSuite->count - testSuite->failCount; const char* testWord = passCount == 1 ? "test" : "tests"; CuStringAppendFormat(details, "OK (%d %s) ", passCount, testWord); } else{ if (testSuite->failCount == 1) CuStringAppend(details, "There was 1 failure: "); else CuStringAppendFormat(details, "There were %d failures: ", testSuite->failCount);

for (i = 0 ; i < testSuite->count ; ++i){ CuTest* testCase = testSuite->list[i]; if (testCase->failed){ failCount++; CuStringAppendFormat(details, "%d) %s: %s ", failCount, testCase->name, testCase->message); } } CuStringAppend(details, " !!!FAILURES!!! ");

CuStringAppendFormat(details, "Runs: %d ", testSuite->count); CuStringAppendFormat(details, "Passes: %d ", testSuite->count - testSuite->failCount); CuStringAppendFormat(details, "Fails: %d ", testSuite->failCount); } }

hashMap.h

#ifndef HASH_MAP_H #define HASH_MAP_H

#define HASH_FUNCTION hashFunction1 #define MAX_TABLE_LOAD .75

typedef struct HashMap HashMap; typedef struct HashLink HashLink;

struct HashLink { char* key; int value; HashLink* next; };

struct HashMap { HashLink** table; // Number of links in the table. int size; // Number of buckets in the table. int capacity; };

HashMap* hashMapNew(int capacity); void hashMapDelete(HashMap* map); int* hashMapGet(HashMap* map, const char* key); void hashMapPut(HashMap* map, const char* key, int value); void hashMapRemove(HashMap* map, const char* key); int hashMapContainsKey(HashMap* map, const char* key);

int hashMapSize(HashMap* map); int hashMapCapacity(HashMap* map); int hashMapEmptyBuckets(HashMap* map); float hashMapTableLoad(HashMap* map); void hashMapPrint(HashMap* map);

#endif

?hashMap.c

#include "hashMap.h" #include #include #include #include

int hashFunction1(const char* key) { int r = 0; for (int i = 0; key[i] != '\0'; i++){ r += key[i]; } return r; }

int hashFunction2(const char* key) { int r = 0; for (int i = 0; key[i] != '\0'; i++){ r += (i + 1) * key[i]; } return r; }

/** * Creates a new hash table link with a copy of the key string. * @param key Key string to copy in the link. * @param value Value to set in the link. * @param next Pointer to set as the link's next. * @return Hash table link allocated on the heap. */ HashLink* hashLinkNew(const char* key, int value, HashLink* next) { HashLink* link = malloc(sizeof(HashLink)); link->key = malloc(sizeof(char) * (strlen(key) + 1)); strcpy(link->key, key); link->value = value; link->next = next; return link; }

/** * Free the allocated memory for a hash table link created with hashLinkNew. * @param link */ static void hashLinkDelete(HashLink* link) { free(link->key); free(link); }

/** * Initializes a hash table map, allocating memory for a link pointer table with * the given number of buckets. * @param map * @param capacity The number of table buckets. */ void hashMapInit(HashMap* map, int capacity) { map->capacity = capacity; map->size = 0; map->table = malloc(sizeof(HashLink*) * capacity); for (int i = 0; i < capacity; i++){ map->table[i] = NULL; } }

/** * Removes all links in the map and frees all allocated memory. You can use * hashLinkDelete to free the links. * @param map */ void hashMapCleanUp(HashMap* map) { // FIXME: implement }

/** * Creates a hash table map, allocating memory for a link pointer table with * the given number of buckets. * @param capacity The number of buckets. * @return The allocated map. */ HashMap* hashMapNew(int capacity) { HashMap* map = malloc(sizeof(HashMap)); hashMapInit(map, capacity); return map; }

/** * Removes all links in the map and frees all allocated memory, including the * map itself. * @param map */ void hashMapDelete(HashMap* map) { hashMapCleanUp(map); free(map); }

/** * Returns a pointer to the value of the link with the given key. Returns NULL * if no link with that key is in the table. * Use HASH_FUNCTION(key) and the map's capacity to find the index of the * correct linked list bucket. Also make sure to search the entire list. * @param map * @param key * @return Link value or NULL if no matching link. */ int* hashMapGet(HashMap* map, const char* key) { // FIXME: implement return NULL; }

/** * Resizes the hash table to have a number of buckets equal to the given * capacity. After allocating the new table, all of the links need to be * rehashed into it because the capacity has changed. * Remember to free the old table and any old links if you use hashMapPut to * rehash them. * @param map * @param capacity The new number of buckets. */ void resizeTable(HashMap* map, int capacity) { // FIXME: implement }

/** * Updates the given key-value pair in the hash table. If a link with the given * key already exists, this will just update the value. Otherwise, it will * create a new link with the given key and value and add it to the table * bucket's linked list. You can use hashLinkNew to create the link. * Use HASH_FUNCTION(key) and the map's capacity to find the index of the * correct linked list bucket. Also make sure to search the entire list. * @param map * @param key * @param value */ void hashMapPut(HashMap* map, const char* key, int value) { // FIXME: implement }

/** * Removes and frees the link with the given key from the table. If no such link * exists, this does nothing. Remember to search the entire linked list at the * bucket. You can use hashLinkDelete to free the link. * @param map * @param key */ void hashMapRemove(HashMap* map, const char* key) { // FIXME: implement }

/** * Returns 1 if a link with the given key is in the table and 0 otherwise. * Use HASH_FUNCTION(key) and the map's capacity to find the index of the * correct linked list bucket. Also make sure to search the entire list. * @param map * @param key * @return 1 if the key is found, 0 otherwise. */ int hashMapContainsKey(HashMap* map, const char* key) { // FIXME: implement return 0; }

/** * Returns the number of links in the table. * @param map * @return Number of links in the table. */ int hashMapSize(HashMap* map) { // FIXME: implement return 0; }

/** * Returns the number of buckets in the table. * @param map * @return Number of buckets in the table. */ int hashMapCapacity(HashMap* map) { // FIXME: implement return 0; }

/** * Returns the number of table buckets without any links. * @param map * @return Number of empty buckets. */ int hashMapEmptyBuckets(HashMap* map) { // FIXME: implement return 0; }

/** * Returns the ratio of (number of links) / (number of buckets) in the table. * Remember that the buckets are linked lists, so this ratio tells you nothing * about the number of empty buckets. Remember also that the load is a floating * point number, so don't do integer division. * @param map * @return Table load. */ float hashMapTableLoad(HashMap* map) { // FIXME: implement return 0; }

/** * Prints all the links in each of the buckets in the table. * @param map */ void hashMapPrint(HashMap* map) { for (int i = 0; i < map->capacity; i++){ HashLink* link = map->table[i]; if (link != NULL){ printf(" Bucket %i ->", i); while (link != NULL){ printf(" (%s, %d) ->", link->key, link->value); link = link->next; } } } printf(" "); }

spellChecker.c

#include "hashMap.h" #include #include #include #include #include

/** * Allocates a string for the next word in the file and returns it. This string * is null terminated. Returns NULL after reaching the end of the file. * @param file * @return Allocated string or NULL. */ char* nextWord(FILE* file) { int maxLength = 16; int length = 0; char* word = malloc(sizeof(char) * maxLength); while (1){ char c = fgetc(file); if ((c >= '0'&& c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '\''){ if (length + 1 >= maxLength){ maxLength *= 2; word = realloc(word, maxLength); } word[length] = c; length++; } else if (length > 0 || c == EOF){ break; } } if (length == 0){ free(word); return NULL; } word[length] = '\0'; return word; }

/** * Loads the contents of the file into the hash map. * @param file * @param map */ void loadDictionary(FILE* file, HashMap* map) { // FIXME: implement }

/** * Prints the concordance of the given file and performance information. Uses * the file input1.txt by default or a file name specified as a command line * argument. * @param argc * @param argv * @return */ int main(int argc, const char** argv) { // FIXME: implement HashMap* map = hashMapNew(1000); FILE* file = fopen("dictionary.txt", "r"); clock_t timer = clock(); loadDictionary(file, map); timer = clock() - timer; printf("Dictionary loaded in %f seconds ", (float)timer / (float)CLOCKS_PER_SEC); fclose(file); char inputBuffer[256]; int quit = 0; while (!quit){ printf("Enter a word or \"quit\" to quit: "); scanf("%s", inputBuffer); // Implement the spell checker code here.. if (strcmp(inputBuffer, "quit") == 0){ quit = 1; } } hashMapDelete(map); return 0; }

tests.c

#include "CuTest.h" #include "hashMap.h" #include #include #include #include

// --- Test Helpers ---

typedef struct HistLink HistLink; typedef struct Histogram Histogram;

struct HistLink { char* key; int count; HistLink* next; };

struct Histogram { HistLink* head; int size; };

void histInit(Histogram* hist) { hist->head = NULL; hist->size = 0; }

void histCleanUp(Histogram* hist) { HistLink* link = hist->head; while (link != NULL){ HistLink* next = link->next; free(link); link = next; } }

void histAdd(Histogram* hist, char* key) { HistLink* link = hist->head; while (link != NULL){ if (strcmp(key, link->key) == 0 ){ link->count++; return; } link = link->next; } link = malloc(sizeof(HistLink)); link->key = key; link->count = 1; link->next = hist->head; hist->head = link; hist->size++; }

/** * Counts the number of times each key appears in the table. * @param hist * @param map */ void histFromTable(Histogram* hist, HashMap* map) { histInit(hist); for (int i = 0; i < map->capacity; i++){ HashLink* link = map->table[i]; while (link != NULL){ histAdd(hist, link->key); link = link->next; } } }

/** * Asserts that each key is unique (count is 1 for each key). * @param test * @param hist */ void assertHistCounts(CuTest* test, Histogram* hist) { HistLink* link = hist->head; while (link != NULL){ CuAssertIntEquals(test, 1, link->count); link = link->next; } }

// --- Hash Map tests --- /* * Test cases: * - At most one link in each bucket under threshold. * - At most one link in each bucket over threshold. * - Multiple links in some buckets under threshold. * - Multiple links in some buckets over threshold. * - Multiple links in some buckets over threshold with duplicates. */

/** * Tests all hash map functions after adding and removing all of the given keys * and values. * @param test * @param links The key-value pairs to be added and removed. * @param notKeys Some keys not in the table to test contains and get. * @param numLinks The number of key-value pairs to be added and removed. * @param numNotKeys The number of keys not in the table. * @param numBuckets The initial number of buckets (capacity) in the table. */ void testCase(CuTest* test, HashLink* links, const char** notKeys, int numLinks, int numNotKeys, int numBuckets) { HashMap* map = hashMapNew(numBuckets); Histogram hist; // Add links for (int i = 0; i < numLinks; i++){ hashMapPut(map, links[i].key, links[i].value); } // Print table printf(" After adding all key-value pairs:"); hashMapPrint(map); // Check size CuAssertIntEquals(test, numLinks, hashMapSize(map)); // Check capacity CuAssertIntEquals(test, map->capacity, hashMapCapacity(map)); // Check empty buckets int sum = 0; for (int i = 0; i < map->capacity; i++) { if (map->table[i] == NULL){ sum++; } } CuAssertIntEquals(test, sum, hashMapEmptyBuckets(map)); // Check table load CuAssertIntEquals(test, (float)numLinks / map->capacity, hashMapTableLoad(map)); // Check contains and get on valid keys. for (int i = 0; i < numLinks; i++){ CuAssertIntEquals(test, 1, hashMapContainsKey(map, links[i].key)); int* value = hashMapGet(map, links[i].key); CuAssertPtrNotNull(test, value); CuAssertIntEquals(test, links[i].value, *value); } // Check contains and get on invalid keys. for (int i = 0; i < numNotKeys; i++){ CuAssertIntEquals(test, 0, hashMapContainsKey(map, notKeys[i])); CuAssertPtrEquals(test, NULL, hashMapGet(map, notKeys[i])); } // Check that all links are present and have a unique key. histFromTable(&hist, map); CuAssertIntEquals(test, numLinks, hist.size); assertHistCounts(test, &hist); histCleanUp(&hist); // Remove keys for (int i = 0; i < numLinks; i++){ hashMapRemove(map, links[i].key); } // Print table printf(" After removing all key-value pairs:"); hashMapPrint(map); // Check size CuAssertIntEquals(test, 0, hashMapSize(map)); // Check capacity CuAssertIntEquals(test, map->capacity, hashMapCapacity(map)); // Check empty buckets CuAssertIntEquals(test, map->capacity, hashMapEmptyBuckets(map)); // Check table load CuAssertIntEquals(test, 0, hashMapTableLoad(map)); // Check contains and get on valid keys. for (int i = 0; i < numLinks; i++){ CuAssertIntEquals(test, 0, hashMapContainsKey(map, links[i].key)); CuAssertPtrEquals(test, NULL, hashMapGet(map, links[i].key)); } // Check contains and get on invalid keys. for (int i = 0; i < numNotKeys; i++){ CuAssertIntEquals(test, 0, hashMapContainsKey(map, notKeys[i])); CuAssertPtrEquals(test, NULL, hashMapGet(map, notKeys[i])); } // Check that there are no links in the table. histFromTable(&hist, map); CuAssertIntEquals(test, 0, hist.size); assertHistCounts(test, &hist); histCleanUp(&hist); hashMapDelete(map); }

/** * Tests hash map functions for a table with no more than one link * in each bucket and without hitting the table load threshold. * @param test */ void testSingleUnder(CuTest* test) { printf(" --- Testing single-link chains under threshold --- "); HashLink links[] = { { .key = "a", .value = 0, .next = NULL }, { .key = "c", .value = 1, .next = NULL }, { .key = "d", .value = 2, .next = NULL }, { .key = "f", .value = 3, .next = NULL }, { .key = "g", .value = 4, .next = NULL } }; const char* notKeys[] = { "b", "e", "h" }; testCase(test, links, notKeys, 5, 3, 10); }

/** * Tests hash map functions for a table with no more than one link * in each bucket while hitting the table load threshold. * @param test */ void testSingleOver(CuTest* test) { printf(" --- Testing single-link chains over threshold --- "); HashLink links[] = { { .key = "a", .value = 0, .next = NULL }, { .key = "c", .value = 1, .next = NULL }, { .key = "d", .value = 2, .next = NULL }, { .key = "f", .value = 3, .next = NULL }, { .key = "g", .value = 4, .next = NULL } }; const char* notKeys[] = { "b", "e", "h" }; testCase(test, links, notKeys, 5, 3, 1); }

/** * Tests hash map functions for a table with 2+ links in some buckets without * hitting the table load threshold. * @param test */ void testMultipleUnder(CuTest* test) { printf(" --- Testing multiple-link chains under threshold --- "); HashLink links[] = { { .key = "ab", .value = 0, .next = NULL }, { .key = "c", .value = 1, .next = NULL }, { .key = "ba", .value = 2, .next = NULL }, { .key = "f", .value = 3, .next = NULL }, { .key = "gh", .value = 4, .next = NULL } }; const char* notKeys[] = { "b", "e", "hg" }; testCase(test, links, notKeys, 5, 3, 10); }

/** * Tests hash map functions for a table with 2+ links in some buckets while * hitting the table load threshold. * @param test */ void testMultipleOver(CuTest* test) { printf(" --- Testing multiple-link chains over threshold --- "); HashLink links[] = { { .key = "ab", .value = 0, .next = NULL }, { .key = "c", .value = 1, .next = NULL }, { .key = "ba", .value = 2, .next = NULL }, { .key = "f", .value = 3, .next = NULL }, { .key = "gh", .value = 4, .next = NULL } }; const char* notKeys[] = { "b", "e", "hg" }; testCase(test, links, notKeys, 5, 3, 1); }

/** * Tests that values are updated when inserting with a key already in the table. * Also tests that keys remain unique after insertion (no duplicate links). * @param test */ void testValueUpdate(CuTest* test) { int numLinks = 5; printf(" --- Testing value updates --- "); HashLink links[] = { { .key = "ab", .value = 0, .next = NULL }, { .key = "c", .value = 1, .next = NULL }, { .key = "ba", .value = 2, .next = NULL }, { .key = "ab", .value = 3, .next = NULL }, { .key = "gh", .value = 4, .next = NULL } }; HashMap* map = hashMapNew(1); // Add links for (int i = 0; i < numLinks; i++){ hashMapPut(map, links[i].key, links[i].value); } // Print table printf(" After adding all key-value pairs:"); hashMapPrint(map); int* value = hashMapGet(map, "ab"); CuAssertPtrNotNull(test, value); CuAssertIntEquals(test, 3, *value); Histogram hist; histFromTable(&hist, map); CuAssertIntEquals(test, numLinks - 1, hist.size); assertHistCounts(test, &hist); histCleanUp(&hist); hashMapDelete(map); }

// --- Test Suite ---

void addAllTests(CuSuite* suite) { SUITE_ADD_TEST(suite, testSingleUnder); SUITE_ADD_TEST(suite, testSingleOver); SUITE_ADD_TEST(suite, testMultipleUnder); SUITE_ADD_TEST(suite, testMultipleOver); SUITE_ADD_TEST(suite, testValueUpdate); }

int main() { CuSuite* suite = CuSuiteNew(); addAllTests(suite); CuSuiteRun(suite); CuString* output = CuStringNew(); CuSuiteSummary(suite, output); CuSuiteDetails(suite, output); printf(" %s ", output->buffer); CuStringDelete(output); CuSuiteDelete(suite); return 0; }

?main.c

#include "hashMap.h" #include #include #include #include #include

/** * Allocates a string for the next word in the file and returns it. This string * is null terminated. Returns NULL after reaching the end of the file. * @param file * @return Allocated string or NULL. */ char* nextWord(FILE* file) { int maxLength = 16; int length = 0; char* word = malloc(sizeof(char) * maxLength); while (1){ char c = fgetc(file); if ((c >= '0'&& c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '\''){ if (length + 1 >= maxLength){ maxLength *= 2; word = realloc(word, maxLength); } word[length] = c; length++; } else if (length > 0 || c == EOF){ break; } } if (length == 0){ free(word); return NULL; } word[length] = '\0'; return word; }

/** * Prints the concordance of the given file and performance information. Uses * the file input1.txt by default or a file name specified as a command line * argument. * @param argc * @param argv * @return */ int main(int argc, const char** argv) { // FIXME: implement const char* fileName = "input1.txt"; if (argc > 1){ fileName = argv[1]; } printf("Opening file: %s ", fileName); clock_t timer = clock(); HashMap* map = hashMapNew(10); // --- Concordance code begins here --- // Be sure to free the word after you are done with it here. // --- Concordance code ends here --- hashMapPrint(map); timer = clock() - timer; printf(" Ran in %f seconds ", (float)timer / (float)CLOCKS_PER_SEC); printf("Empty buckets: %d ", hashMapEmptyBuckets(map)); printf("Number of links: %d ", hashMapSize(map)); printf("Number of buckets: %d ", hashMapCapacity(map)); printf("Table load: %f ", hashMapTableLoad(map)); hashMapDelete(map); return 0; }

input1.txt

As the wind does blow Across the trees I see the Buds blooming in May

I walk across sand And find myself blistering In the hot hot heat

Falling to the ground I watch a leaf settle down In a bed of brown.

It's cold and I wait For someone to shelter me And take me from here.

input2.txt

Call me Ishmael Some years ago never mind how long precisely having little or no money in my purse and nothing particular to interest me on shore I thought I would sail about a little and see the watery part of the world It is a way I have of driving off the spleen and regulating the circulation Whenever I find myself growing grim about the mouth whenever it is a damp drizzly November in my soul whenever I find myself involuntarily pausing before coffin warehouses and bringing up the rear of every funeral I meet and especially whenever my hypos get such an upper hand of me that it requires a strong moral principle to prevent me from deliberately stepping into the street and methodically knocking peoples hats off then I account it high time to get to sea as soon as I can This is my substitute for pistol and ball With a philosophical flourish Cato throws himself upon his sword I quietly take to the ship There is nothing surprising in this If they but knew it almost all men in their degree some time or other cherish very nearly the same feelings towards the ocean with me There now is your insular city of the Manhattoes belted round by wharves as Indian isles by coral reefs commerce surrounds it with her surf Right and left the streets take you waterward Its extreme downtown is the battery where that noble mole is washed by waves and cooled by breezes which a few hours previous were out of sight of land Look at the crowds of water gazers there

input3.txt

eat ate tea