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#include <iostream>#include <vector>#include <limits>#define DEBUG_TRIAL falseclass Trial{public:const size_t HEIGHT;std::string record;//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.//Eggs is the eggs remaining.//Start is the bottom floor.//End is one above the top floor.const size_t BREAKING_HEIGHT;size_t eggs;size_t start;size_t end;size_t floorsLeft(){return (end-start);}size_t middle(){return start + (floorsLeft()/2UL);}size_t drops = 0;Trial(const size_t BREAKING_HEIGHT, size_t eggs, size_t start, size_t end): BREAKING_HEIGHT(BREAKING_HEIGHT), eggs(eggs), start(start), end(end), HEIGHT(end), record(end, '_'){record[BREAKING_HEIGHT] = 'B'; //Marking the breaking point}bool foundAnswer(){return ((record[0] == 'X') || (record.find("OX")!=std::string::npos));}//returns true if the egg broke.//height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.bool drop(size_t height){#if DEBUG_TRIALstd::cout << "Start: " << start << ". End: " << end << ". Floors Left: " << floorsLeft() << ". Middle Index: " << middle() << std::endl;#endifdrops++;bool cracked = height >= BREAKING_HEIGHT;if(cracked) --eggs;//Update the recordrecord[height] = (height >= BREAKING_HEIGHT)? 'X' : 'O';#if DEBUG_TRIAL//Print the recordstd::cout << record << std::endl;#endifreturn cracked;}size_t nowWhat(){if(foundAnswer()){return drops;}else if(eggs <= 0){ //Ran out of eggsthrow "Algorithm failed! No more eggs!";return 1UL;}else if(eggs > 1){return wrecklessSearch();}else{return safeSearch();}}size_t safeSearch(){if(drop(start)){--end;}else{++start;}return nowWhat();}size_t wrecklessSearch(){//If the egg breaksif(drop(middle())){end -= (floorsLeft()/2UL);}else{ //egg doesn't crackstart += (floorsLeft()/2UL);}return nowWhat();}//returns the amount of drops needed to find the answersize_t search(){return nowWhat();}};//Height is the height of the building in floors.//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.//Eggs is the eggs given.//returns the amount of drops needed to find the answersize_t search(const size_t height, const size_t BREAKING_HEIGHT, size_t eggs){Trial trial(BREAKING_HEIGHT, eggs, 0, height);return trial.search();}class TrialStats {public:size_t min = std::numeric_limits<size_t>::max();size_t max = 0;double mean = -1.0;void printStats(){// Print the resultsstd::cout << "Minimum drops: " << min << std::endl;std::cout << "Maximum drops: " << max << std::endl;std::cout << "Mean drops: " << mean << std::endl;}};//Benchmarks all the possible breaking points of a single building height with a number of eggs.TrialStats trial(const size_t HEIGHT, const size_t eggs){TrialStats stats;int totaldrops = 0;//Test every possible breaking point//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.for (int breakingHeight = 0; breakingHeight < HEIGHT; ++breakingHeight) {size_t drops = search(HEIGHT, breakingHeight, eggs);stats.min = std::min(stats.min, drops);stats.max = std::max(stats.max, drops);totaldrops += drops;}// Calculate the mean number of dropsstats.mean = static_cast<double>(totaldrops) / HEIGHT;return stats;}//Benchmarks a single building height from 1 egg to MAX_EGGSvoid testTower(const size_t height, const size_t MAX_EGGS){//Drop every amount of eggs that you'd need.for (int eggs = 1; eggs <= MAX_EGGS; ++eggs) {std::cout << "Building height: " << height << ". Num eggs: " << eggs << std::endl;TrialStats stats = trial(height, eggs);stats.printStats();std::cout << std::endl << std::endl;}}//Benchmarks all buildings from 0 to MAX_HEIGHTvoid benchmark(const size_t MAX_HEIGHT){const size_t MAX_EGGS = 2;//Test every buildingfor (size_t height = 1; height <= MAX_HEIGHT; ++height) {testTower(height, std::min(height, MAX_EGGS));}}int main() {constexpr size_t MAX_HEIGHT = 36;benchmark(MAX_HEIGHT);return 0;}
#include<iostream>using namespace std;const int rows = 8;const int cols = 8;char chessboard[rows][cols];void setBoard(char chessboard[][cols]);void printBoard(char chessboard[][cols]);void setBoard(char chessboard[][cols]) {for(int i = 0; i < rows; i++) {for(int j = 0; j < cols; j++) {if(i % 2 == 0 && j % 2 == 0) {chessboard[i][j] = 'x';} else {if(i % 2 != 0 && j % 2 == 1) {chessboard[i][j] = 'x';} else {chessboard[i][j] = '-';}}}}return;}void printBoard(char chessboard[][cols]) {for(int i = 0; i < rows; i++) {for(int j = 0; j < cols; j++) {cout << chessboard[i][j] << " ";}cout << endl;}return;}int main(int argc, char const *argv[]){setBoard(chessboard);printBoard(chessboard);return 0;}
#include <iostream>#include <vector>using namespace std;void swap(int *a, int *b){int temp = *b;*b = *a;*a = temp;}void heapify(vector<int> &hT, int i){int size = hT.size();int largest = i;int l = 2 * i + 1;int r = 2 * i + 2;if (l < size && hT[l] > hT[largest])largest = l;if (r < size && hT[r] > hT[largest])largest = r;if (largest != i){swap(&hT[i], &hT[largest]);heapify(hT, largest);}}void insert(vector<int> &hT, int newNum){int size = hT.size();if (size == 0){hT.push_back(newNum);}else{hT.push_back(newNum);for (int i = size / 2 - 1; i >= 0; i--){heapify(hT, i);}}}void deleteNode(vector<int> &hT, int num){int size = hT.size();int i;for (i = 0; i < size; i++){if (num == hT[i])break;}swap(&hT[i], &hT[size - 1]);hT.pop_back();for (int i = size / 2 - 1; i >= 0; i--){heapify(hT, i);}}void printArray(vector<int> &hT){for (int i = 0; i < hT.size(); ++i)cout << hT[i] << " ";cout << "\n";}int main(){vector<int> heapTree;insert(heapTree, 3);insert(heapTree, 4);insert(heapTree, 9);insert(heapTree, 5);insert(heapTree, 2);cout << "Max-Heap array: ";printArray(heapTree);deleteNode(heapTree, 4);cout << "After deleting an element: ";printArray(heapTree);}
#include <iostream>#include "PlaylistNode.h"using namespace std;void PrintMenu(string title);int main() {string plTitle;cout << "Enter playlist's title:" << endl;getline(cin, plTitle);PrintMenu(plTitle);return 0;}void PrintMenu(string title) {Playlist list;string id;string sname;string aname;int length;int oldPos;int newPos;char choice;while(true) {cout << endl << title << " PLAYLIST MENU" << endl;cout << "a - Add song" << endl;cout << "d - Remove song" << endl;cout << "c - Change position of song" << endl;cout << "s - Output songs by specific artist" << endl;cout << "t - Output total time of playlist (in seconds)" << endl;cout << "o - Output full playlist" << endl;cout << "q - Quit" << endl << endl;cout << "Choose an option:" << endl;cin >> choice;cin.ignore();if (choice == 'q') {exit(1);}else if (choice == 'a') {cout << "\nADD SONG" << endl;cout << "Enter song's unique ID: ";cin >> id;cin.ignore();cout << "Enter song's name: ";getline(cin,sname);cout << "Enter artist's name: ";getline(cin,aname);cout << "Enter song's length (in seconds): ";cin >> length;list.AddSong(id, sname, aname, length);}else if (choice == 'd') {cout << "\nREMOVE SONG" << endl;cout << "Enter song's unique ID: ";cin >> id;list.RemoveSong(id);}else if (choice == 'c') {cout << "\nCHANGE POSITION OF SONG" << endl;cout << "Enter song's current position: ";cin >> oldPos;cout << "Enter new position for song: ";cin >> newPos;list.ChangePosition(oldPos, newPos);}else if (choice == 's') {cout << "\nOUTPUT SONGS BY SPECIFIC ARTIST" << endl;cout << "Enter artist's name: ";getline(cin, aname);list.SongsByArtist(aname);}else if (choice == 't') {cout << "\nOUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)" << endl;cout << "Total time: " << list.TotalTime() << " seconds" << endl;}else if (choice == 'o') {cout << endl << title << " - OUTPUT FULL PLAYLIST" << endl;list.PrintList();}else {cout << "Invalid menu choice! Please try again." << endl;}}}
#include <iostream>using namespace std;/* Function: get_coeffParameters: double& coeff, int pos passed from bb_4acReturn: type is void so no return, but does ask for user to input data that establishes what a b and c are.*/void get_coeff(double& coeff, int pos) {char position;if(pos == 1) {position = 'a';} else if(pos == 2) { //a simple system to determine what coefficient the program is asking for.position = 'b';} else {position = 'c';}cout << "Enter the co-efficient " << position << ":"; //prompt to input coeffcoeff = 5; //input coeff}/* Function: bb_4acParameters: no parameters passed from main, but 3 params established in function, double a, b, c.Return: b * b - 4 * a * c*/double bb_4ac() {double a, b, c; //coefficients of a quadratic equationget_coeff(a, 1); // call function 1st timeget_coeff(b, 2); // call function 2nd timeget_coeff(c, 3); // call function 3rd timereturn b * b - 4 * a * c; //return b * b - 4 * a * c}int main() {cout << "Function to calculate the discriminant of the equation. . . " << endl;double determinate = bb_4ac(); //assign double determinate to bb_4ac functioncout << "The discriminant for given values is: " << determinate << endl; //output the determinate!}
/*Good morning! Here's your coding interview problem for today.This problem was asked by Stripe.Given an array of integers, find the first missing positive integer in linear time and constant space. In other words, find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well.For example, the input [3, 4, -1, 1] should give 2. The input [1, 2, 0] should give 3.You can modify the input array in-place.*/#include <iostream>using namespace std;int calcMissing(int* input, int size){int sum = 0;int n = 1; //add one to account for missing valuefor(int i = 0; i < size; i++){if(input[i] > 0){sum += input[i];n++;}}//If no numbers higher than 0, answer is 1if(sum == 0)return 1;return (n*(n+1)/2) - sum; //Formula is expectedSum - actualSum/* expectedSum = n*(n+1)/2, the formula for sum(1, n) */}int main(){cout << calcMissing(new int[4]{3, 4, -1, 1}, 4) << endl;cout << calcMissing(new int[3]{1, 2, 0}, 3) << endl;//No positive numberscout << calcMissing(new int[1]{0}, 1) << endl;}