Can someone help me solve this assignment?

//CSE240 Spring 2019 HW4

// Enter your name here // State the IDE that you use: Visual Studio or GCC

#include #include

#pragma warning(disable : 4996) // compiler directive for Visual Studio only

// Read before you start: // You are given a partially complete program. Complete the functions in order for this program to work successfully. // All instructions are given above the required functions, please read them and follow them carefully. // You shoud not modify the function return types or parameters. // You can assume that all inputs are valid. Ex: If prompted for an integer, the user will input an integer. // You can use only the strlen() of strings.h library to check string length. Do not use any other string functions // because you are supposed to use pointers for this homework. // **** DO NOT use arrays to store or to index the characters in the string ****

// Global Macro Values. They are used to define the size of 2D array of characters #define NUM_STRINGS 4 #define STRING_LENGTH 50

// Forward Declarations void initializeStrings(char[NUM_STRINGS][STRING_LENGTH]); void printStrings(char[NUM_STRINGS][STRING_LENGTH]); void encryptStrings(char[NUM_STRINGS][STRING_LENGTH], int); void decryptStrings(char[NUM_STRINGS][STRING_LENGTH], int); void reverseStrings(char strings[NUM_STRINGS][STRING_LENGTH]); char* reverseOneString(char s[STRING_LENGTH]); int isPalindrome(char s[STRING_LENGTH]);

// Problem 1: initializeStrings (5 points) // Use pointer p to traverse the 2D array of characters variable 'strings' (input from user in main() ) and set all characters in each // array to a null terminator so that there is a 4 row and 50 column 2D array full of null terminators. // The null terminator '\0' is used to denote the end of a string. void initializeStrings(char strings[NUM_STRINGS][STRING_LENGTH]) { char *ptr = &strings[0][0]; // enter code here

}

// Problem 2: printStrings (5 points) // Use pointer p to traverse the 2D character array "strings" and print each string. // See the example outputs provided in the word document. Each string should be printed on a new line. void printStrings(char strings[NUM_STRINGS][STRING_LENGTH]) { char *ptr = &strings[0][0]; // enter code here

}

// Problem 3: reverseOneString (15 points) // Reverse the string s by using pointer. // Use pointer p and 'temp' char to swap 1st char with last, then 2nd char with (last-1) and so on.. // Finally return pointer p which points to start of the reversed string. // You may declare and use more pointers if needed. // Hint: You might want to check if your logic works with even as well as odd length string. // You can write test code to print out the reversed string to check if your function works. (Don't include it in final submission) char* reverseOneString(char s[STRING_LENGTH]) { char temp; // not necessary to use this variable char *p = &s[0]; // pointer to start of string // enter code here

return p; }

// Problem 4: reverseStrings (5 points) // Reverse all the strings in 'strings[][]' // For each string in 'strings', use the reverseOneString() to reverse it. // You may declare and use more pointers if needed. void reverseStrings(char strings[NUM_STRINGS][STRING_LENGTH]) { char *ptr = &strings[0][0]; // enter code here

}

// Problem 5: encryptStrings (5 points) // Use pointer ptr to traverse the 2D character array 'strings' and encrypt each string in 2 step as follows- // 1) Reverse the strings. Hint: Use 'reverseStrings()' for this step. // 2) Shift the characters forward by the integer value of 'key'. // If the string is "hello" and key = 2, reversing will get you "olleh" and adding key to it will result in "qnnfj". // Once the value of 'key' gets larger, you will extend past alphabetical characters and reach non-alphabetical characters. Thats ok. // NOTE: DO NOT encrypt the null terminator character. Use the null terminator to find the end string. // If you could not implement reverseStrings(), skip using it in this function. You will receive partial credit. void encryptStrings(char strings[NUM_STRINGS][STRING_LENGTH], int key) { char *p = &strings[0][0]; // enter code here

} // Problem 6: decryptStrings (5 points) // HINT: This should be very similiar to the encryption function defined above in encryptStrings(). // Use pointer p to traverse the 2D character array 'strings' and decrypt each string in 2 step as follows- // 1) Shift the characters backward by the integer value of 'key'. // 2) Reverse the strings. Hint: Use 'reverseStrings()' for this step. // NOTE: DO NOT decrypt the null characters. // If you could not implement reverseStrings(), skip using it in this function. You will receive partial credit. void decryptStrings(char strings[NUM_STRINGS][STRING_LENGTH], int key) { char *ptr = &strings[0][0]; // enter code here

}

// Problem 7: isPalindrome (10 points) // Return 1 if string s is palindrome. // Parse through the string to check if 1st char==last char, 2nd char == (last-1) char, and so on.. // Return 1 if string is palindrome. Return 0 if string is not palindrome. // A palindrome is a sequence of characters which when reversed, is the same sequence of characters. // Palindrome string examples: rotor, noon, madam // Note: you may use reverseOneString() here but it is not necessary to use it. int isPalindrome(char s[STRING_LENGTH]) { char *p = s; int palindrome = 1; // edit if needed // enter code here

return palindrome; }

// You should study and understand how main() works. // *** DO NOT modify it in any way *** int main() { char strings[NUM_STRINGS][STRING_LENGTH]; // will store four strings each with a max length of 34 int i, key; char input[STRING_LENGTH]; printf("CSE240 HW4: Pointers "); initializeStrings(strings); for (i = 0; i < NUM_STRINGS; i++) { printf("Enter a string: "); // prompt for string fgets(input, sizeof(input), stdin); // store input string input[strlen(input) - 1] = '\0'; // convert trailing ' ' char to '\0' (null terminator) strcpy(strings[i], input); // copy input to 2D strings array } printf(" Enter a key value for encryption: "); // prompt for integer key scanf("%d", &key); encryptStrings(strings, key); printf(" Encrypted Strings: "); printStrings(strings); decryptStrings(strings, key); printf(" Decrypted Strings: "); printStrings(strings);

getchar(); // flush out newline ' ' char

printf(" Checking for palindrome. Enter a string: "); // prompt for string fgets(input, sizeof(input), stdin); // store input string input[strlen(input) - 1] = '\0'; // convert trailing ' ' char to '\0' (null terminator)

if (isPalindrome(input)) printf("The string is a palindrome"); else printf("The string is not a palindrome");

getchar(); // keep VS console open return 0; }