This homework assignment is to make the functions in the classes faster while passsing the tests in the main.cpp file: Files given are: main.cpp & trendtracker.h with some text files.. Instructions are as follows: Create a new C++ source file namedtrendtracker.cpp that implements the Trendtracker class, so that trendtracker.cpp and the pro- vided files compile into a program that runs with no failed tests. Submit the source file trendtracker.cpp. //******************** main.cpp ********************//

#include  #include  #include  #include  #include  #include "trendtracker.h" using namespace std; inline void _test(const char* expression, const char* file, int line) { cerr << "test(" << expression << ") failed in file " << file; cerr << ", line " << line << "." << endl; abort(); } #define test(EXPRESSION) ((EXPRESSION) ? (void)0 : _test(#EXPRESSION, __FILE__, __LINE__)) int main() { // Setup vector R; string s, line; // Test constructor, size(), popularity(), tweeted() Trendtracker T1("small.txt"); test(T1.size() == 4); test(T1.popularity("#algorithms") == 0); test(T1.popularity("#cs4all") == 0); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 0); test(T1.popularity("#C++") == 0); T1.tweeted("#programming"); test(T1.popularity("#algorithms") == 0); test(T1.popularity("#cs4all") == 0); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 1); test(T1.popularity("#C++") == 0); T1.tweeted("#programming"); test(T1.popularity("#algorithms") == 0); test(T1.popularity("#cs4all") == 0); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 2); test(T1.popularity("#C++") == 0); T1.tweeted("#programming"); test(T1.popularity("#algorithms") == 0); test(T1.popularity("#cs4all") == 0); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); T1.tweeted("#cs4all"); test(T1.popularity("#algorithms") == 0); test(T1.popularity("#cs4all") == 1); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); T1.tweeted("#algorithms"); test(T1.popularity("#algorithms") == 1); test(T1.popularity("#cs4all") == 1); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); T1.tweeted("#cs4all"); test(T1.popularity("#algorithms") == 1); test(T1.popularity("#cs4all") == 2); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); T1.tweeted("#datastructures"); test(T1.popularity("#algorithms") == 1); test(T1.popularity("#cs4all") == 2); test(T1.popularity("#datastructures") == -1); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); Trendtracker T2("small.txt"); T2.tweeted("#programming"); T2.tweeted("#programming"); T2.tweeted("#programming"); T2.tweeted("#programming"); T2.tweeted("#programming"); T2.tweeted("#C++"); T2.tweeted("#C++"); T2.tweeted("#C++"); T2.tweeted("#C++"); T2.tweeted("#cs4all"); T2.tweeted("#cs4all"); T2.tweeted("#cs4all"); T2.tweeted("#algorithms"); T2.tweeted("#algorithms"); test(T2.popularity("#algorithms") == 2); test(T2.popularity("#cs4all") == 3); test(T2.popularity("#programming") == 5); test(T2.popularity("#C++") == 4); // Enforce no usage of global variables test(T1.popularity("#algorithms") == 1); test(T1.popularity("#cs4all") == 2); test(T1.popularity("#programming") == 3); test(T1.popularity("#C++") == 0); // Test top_trend(), top_three_trends() Trendtracker T3("small.txt"); T3.top_three_trends(R); test(R.size() == 3); T3.tweeted("#programming"); test(T3.top_trend() == "#programming"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#programming"); T3.tweeted("#C++"); T3.tweeted("#C++"); test(T3.top_trend() == "#C++"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#C++"); test(R[1] == "#programming"); T3.tweeted("#algorithms"); T3.tweeted("#algorithms"); T3.tweeted("#algorithms"); test(T3.top_trend() == "#algorithms"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#algorithms"); test(R[1] == "#C++"); test(R[2] == "#programming"); T3.tweeted("#cs4all"); T3.tweeted("#cs4all"); T3.tweeted("#cs4all"); T3.tweeted("#cs4all"); test(T3.top_trend() == "#cs4all"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#cs4all"); test(R[1] == "#algorithms"); test(R[2] == "#C++"); // At this point: // cs4all: 4 // algorithms: 3 // C++: 2 // programming: 1 T3.tweeted("#programming"); T3.tweeted("#programming"); T3.tweeted("#programming"); T3.tweeted("#programming"); test(T3.top_trend() == "#programming"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#programming"); test(R[1] == "#cs4all"); test(R[2] == "#algorithms"); // At this point: // programming: 5 // cs4all: 4 // algorithms: 3 // C++: 2 T3.tweeted("#cs4all"); T3.tweeted("#cs4all"); T3.tweeted("#algorithms"); test(T3.top_trend() == "#cs4all"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#cs4all"); test(R[1] == "#programming"); test(R[2] == "#algorithms"); // At this point: // cs4all: 6 // programming: 5 // algorithms: 4 // C++: 2 for (int i = 0; i < 10000; ++i) T3.tweeted("#C++"); test(T3.top_trend() == "#C++"); T3.top_three_trends(R); test(R.size() == 3); test(R[0] == "#C++"); test(R[1] == "#cs4all"); test(R[2] == "#programming"); Trendtracker T4("hashtags.txt"); test(T4.size() == 300000); ifstream f; f.open("tweeted.txt"); assert(f.is_open()); // If this fails, you're missing tweeted.txt while (getline(f, line)) T4.tweeted(line); f.close(); test(T4.popularity("#programming") == 10); test(T4.popularity("#computer") == 9); test(T4.popularity("#is") == 8); test(T4.popularity("#very") == 7); test(T4.popularity("#fun") == 6); test(T4.popularity("#but") == 5); test(T4.popularity("#sometimes") == 5); test(T4.popularity("#can") == 5); test(T4.popularity("#be") == 5); test(T4.popularity("#challenging") == 5); test(T4.top_trend() == "#programming"); T4.top_three_trends(R); test(R[0] == "#programming"); test(R[1] == "#computer"); test(R[2] == "#is"); // Test a Trendtracker with a single hashtag Trendtracker T5("tiny.txt"); test(T5.size() == 1); test(T5.popularity("#solo") == 0); test(T5.popularity("#duo") == -1); T5.tweeted("#solo"); test(T5.popularity("#solo") == 1); test(T5.popularity("#duo") == -1); test(T5.top_trend() == "#solo"); T5.top_three_trends(R); test(R.size() == 1); test(R[0] == "#solo"); cout << "Assignment complete." << endl; } //*************** trendtracker.h **************// 

#ifndef TRENDTRACKER_H #define TRENDTRACKER_H #include  #include  #include  #include  using namespace std; class Trendtracker { // For the mandatory running times below: // n is the number of hashtags in the Trendtracker. public: // Creates a Trendtracker containing hashtags // found in the provided file. // The file is promised to have the following format: // // string1 // string2 // ... // stringN // // where string1 < string2 < ... < stringN // // Must run in O(n) time. Trendtracker(string filename); // Return the number of hashtags in the Trendtracker. // // Must run in O(1) time. int size(); // Adds 1 to the total number times a hashtag has been tweeted. // If the hashtag does not exist in TrendTracker, does nothing. // // Must run in O(log(n)) time. void tweeted(string ht); // Returns the number of times a hashtag has been tweeted. // If the hashtag does not exist in Trendtracker, returns -1. // // Must run in O(log(n)) time. int popularity(string name); // Returns a most-tweeted hashtag. // If the Trendtracker has no hashtags, returns "". // // Must run in O(1) time. string top_trend(); // Fills the provided vector with the 3 most-tweeted hashtags, // in order from most-tweeted to least-tweeted. // // If there are fewer than 3 hashtags, then the vector is filled // with all hashtags (in most-tweeted to least-tweeted order). // // Must run in O(1) time. void top_three_trends(vector &T); private: // A simple class representing a hashtag and // the number of times it has been tweeted. class Entry { public: string hashtag; int pop; }; // Optional helper method. // Returns the index of E containing an Entry with hashtag ht. // If no such hashtag is found, returns -1. // // Should run in O(log(n)). int search(string ht); // Entries sorted (lexicographically) by hashtag. vector E; // Stores indices of the (up to) three most-tweeted // entries in E. vector S; }; #endif 

//****************** (my current) trendtracker.cpp **************//  

#include "trendtracker.h" #include using namespace std;

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Trendtracker::Trendtracker() { }

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// Inserts a hashtag (tweeted 0 times) into the Trendtracker. // If the hashtag already is in Trendtracker, does nothing. void Trendtracker::insert(string ht) { Entry trend; int i, n = E.size(); trend.hashtag = ht; trend.pop = 0; for (i = 0; i < n; i++) { if (ht == E[i].hashtag) { break; } } if(i == n) E.push_back(trend); //Push the element only if i is equal to n, that is there was no instance of the hastag to be inserted }

/*************************************************************/

// Return the number of hashtags in the Trendtracker. int Trendtracker::size() { return E.size(); }

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// Inserts a hashtag (tweeted 0 times) into the Trendtracker. // If the hashtag already is in Trendtracker, does nothing. void Trendtracker::tweeted(string ht) { int n = E.size(); for (int i = 0; i < n; i++) { if (ht == E[i].hashtag) { E[i].pop++; break; // Breaks if required match found } } }

/*************************************************************/

// Returns the number of times a hashtag has been tweeted. // If the hashtag does not exist in Trendtracker, returns -1. int Trendtracker::popularity(string name) { int i = 0; int n = E.size(); bool check = 0; for (i = 0; i < n; i++) { if (name == E[i].hashtag) { check = 1; break; } } if (check == 1) { return E[i].pop; } else { return -1; } }

/*************************************************************/

// Returns a most-tweeted hashtag. // If the Trendtracker has no hashtags, returns "". string Trendtracker::top_trend() { if(size() == 0) return ""; //return an empty string if empty int i, n, popular; //loops through Trendtracker checking for the hashtag with most tweets for (i = 1, n = E.size(), popular = 0; i < n; i++) { if (E[i].pop > E[popular].pop) popular = i; } return E[popular].hashtag; }

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// Fills the provided vector with the 3 most-tweeted hashtags, // in order from most-tweeted to least-tweeted. // // If there are fewer than 3 hashtags, then the vector is filled // with all hashtags (in most-tweeted to least-tweeted order). void Trendtracker::top_three_trends(vector& T) { T.clear(); //Clears the vector for further use if(size() == 0) return; //Returns if trends are empty int n = E.size(); Entry dummy = {"", -1}; E.push_back(dummy); //Create a dummy entry with a negative value and assume its the largest //first, second and third point to it int i, j, first, second, third; for (i = 0, first = second = third = n; i < n; i++) { if(E[i].pop > E[first].pop) { third = second; second = first; first = i; } else if(E[i].pop > E[second].pop) { third = second; second = i; } else if(E[i].pop > E[third].pop) { third = i; } } T.push_back(E[first].hashtag); if(second != n && second != first) T.push_back(E[second].hashtag); if(third != n && third != second) T.push_back(E[third].hashtag); //Check if the pointers still point to the dummy variable //insert only if it doesn't E.pop_back(); //Remove the dummy element }