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//===============Header File==================#include <iostream>#include <sstream> //stringbuf#include <utility> //exchange//Couple rules://Characters given through the getter functions have to be removed from the buffer.//This is so that bufferEmpty() == buffer.in_avail() > 0 basically always.//skipWhitespace doesn't remove the text from the buffer, but it does return the number of characters.//nextWord will trim whitespace before the word//nextInt will trim non-numbers before the number//hasNextInt and hasNextWord will trim the whitespace. If you think you need it, you should get nextWhitespace before doing any of those.//Whitespace after a word or an int is left on the buffer.//nextWhitespace will (get and) remove whitespace until the end of the line, including the newline character, but stops before the next line.//nextWhitespace won't read the next line when called before the end of the line, and it won't prompt the user for the next line if interactive.//If nextWhitespace is called after reading the end of the line, then it will read a new line into the buffer, which will prompt the user.//It acts like nextLine, but if there's something non-whitespace on the current line it stops there.class Scanner {public:std::stringbuf buffer;std::istream& input;Scanner(std::istream& in = std::cin) : buffer(), input(in) {}//Buffer debuggingbool fillBuffer();bool bufferEmpty();void printBufferEmpty();std::string getBuffer();size_t bufferLength();void printBufferStats();//Intbool hasNextInt();int nextInt();//Wordbool hasNextWord();std::string nextWord();//Linebool hasNextLine();//Whitespacesize_t skipWhitespace(); //Prob should be private, but I don't believe in that private shit.bool hasNextWhitespace();std::string nextWhitespace();std::string nextWhitespaceAll();std::string nextLine();};//===============Source File==================bool Scanner::fillBuffer() { //Returns if it had to get the next line from the input.const bool badInput = input.eof() || input.bad();const bool shouldFillBuffer = bufferEmpty() && !badInput;if (shouldFillBuffer) {std::string line;if (std::getline(input, line)) {buffer.str(buffer.str() + line + "\n");}}return shouldFillBuffer;}bool Scanner::bufferEmpty(){return buffer.str() == "";}void Scanner::printBufferEmpty(){std::cout << "The buffer is " << (bufferEmpty()? "" : "not") << " empty." << std::endl;}std::string Scanner::getBuffer(){return buffer.str();}size_t Scanner::bufferLength(){return buffer.str().length();}void Scanner::printBufferStats(){if(bufferEmpty()){std::cout << "The buffer is \"\"" << std::endl;return;}std::cout << "The length of the buffer is " << bufferLength() << std::endl;if(buffer.sgetc() == '\r'){std::cout << "The buffer is \\r\\n" << std::endl;}else if(buffer.sgetc() == '\n'){std::cout << "The buffer is \\n" << std::endl;}}bool Scanner::hasNextInt() {return hasNextWord() && (std::isdigit(buffer.sgetc()) || buffer.sgetc() == '-');}int Scanner::nextInt() {if (!hasNextInt()) { //Will fill the buffer if not filled. Will also trim whitespace.return 0;}std::string num;size_t charactersRead = 0;while (buffer.in_avail() > 0 && (std::isdigit(buffer.sgetc()) || buffer.sgetc() == '-')) {num += buffer.sbumpc();++charactersRead;}buffer.str(buffer.str().erase(0, charactersRead));return std::stoi(num);}bool Scanner::hasNextWord() {nextWhitespaceAll();return buffer.in_avail() > 0;}std::string Scanner::nextWord() {if (!hasNextWord()) { //Will fill the buffer if not filled. Will also trim whitespace.return "";}std::string word;size_t charactersRead = 0;while (buffer.in_avail() > 0 && !std::isspace(buffer.sgetc())) {word += buffer.sbumpc();++charactersRead;}buffer.str(buffer.str().erase(0, charactersRead));return word;}bool Scanner::hasNextLine() {return (!bufferEmpty()) || fillBuffer();}size_t Scanner::skipWhitespace() { //Returns characters readsize_t charactersRead = 0;while (buffer.in_avail() > 0 && std::isspace(buffer.sgetc())) {buffer.sbumpc();++charactersRead;}return charactersRead;}bool Scanner::hasNextWhitespace(){fillBuffer();return buffer.in_avail() > 0 && std::isspace(buffer.sgetc());}std::string Scanner::nextWhitespace() {if (!hasNextWhitespace()) { //Will fill the buffer if not filledreturn "";}const size_t charactersRead = skipWhitespace();std::string whitespace = buffer.str().substr(charactersRead);buffer.str(buffer.str().erase(0, charactersRead));return whitespace;}std::string Scanner::nextWhitespaceAll(){std::string whitespace;while(hasNextWhitespace()){std::string gottenWhiteSpace = nextWhitespace();whitespace += gottenWhiteSpace;}return whitespace;}std::string Scanner::nextLine(){if (!hasNextLine()) {return "";}fillBuffer();//Swap out the old buffer with an empty buffer, and get the old buffer as a variable.std::string line = std::exchange(buffer, std::stringbuf()).str();//Remove the newline.if(line[line.length() - 1] == '\n' || line[line.length() - 1] == '\r' ) line.pop_back();if(line[line.length() - 1] == '\r' || line[line.length() - 1] == '\n' ) line.pop_back();return line;}//=================Word and Int test=================while(bruh.hasNextInt() || bruh.hasNextWord()){std::cout << "started loop" << std::endl;if(bruh.hasNextInt()){std::cout << "Int: " << bruh.nextInt() << " " << std::endl;}else{std::cout << "Word: " << bruh.nextWord() << " " << std::endl;}bruh.nextWhitespace();}//===================Line test======================for(int count = 1; bruh.hasNextLine(); ++count){std::string line = bruh.nextLine();std::cout << "Line " << count << ": " << line << std::endl;}
//Leif Messinger//Finds all sets of 5 5 letter words that don't have duplicate letters in either themselves or each other.//First it reads the words in and puts them in groups of their bitmasks//After that, we recurse on each group. Before doing that, we remove the group from the set of other groups to check it against.#include <cstdio> //getchar, printf#include <cassert> //assert#include <vector>#include <set>#include <algorithm> //std::copy_if#include <iterator> //std::back_inserter#define CHECK_FOR_CRLF true#define MIN_WORDS 5#define MAX_WORDS 5#define WORD_TOO_LONG(len) (len != 5)const unsigned int charToBitmask(const char bruh){assert(bruh >= 'a' && bruh <= 'z');return (1 << (bruh - 'a'));}void printBitmask(unsigned int bitmask){char start = 'a';while(bitmask != 0){if(bitmask & 1){putchar(start);}bitmask >>= 1;++start;}}//Pointer needs to be deletedconst std::set<unsigned int>* getBitmasks(){std::set<unsigned int>* bitmasksPointer = new std::set<unsigned int>;std::set<unsigned int>& bitmasks = (*bitmasksPointer);unsigned int bitmask = 0;unsigned int wordLength = 0;bool duplicateLetters = false;for(char c = getchar(); c >= 0; c = getchar()){if(CHECK_FOR_CRLF && c == '\r'){continue;}if(c == '\n'){if(!(WORD_TOO_LONG(wordLength) || duplicateLetters)) bitmasks.insert(bitmask);bitmask = 0;wordLength = 0;duplicateLetters = false;continue;}if((bitmask & charToBitmask(c)) != 0) duplicateLetters = true;bitmask |= charToBitmask(c);++wordLength;}return bitmasksPointer;}void printBitmasks(const std::vector<unsigned int>& bitmasks){for(unsigned int bruh : bitmasks){printBitmask(bruh);putchar(','); putchar(' ');}puts("");}//Just to be clear, when I mean "word", I mean a group of words with the same letters.void recurse(std::vector<unsigned int>& oldBitmasks, std::vector<unsigned int> history, const unsigned int currentBitmask){//If there's not enough words leftif(oldBitmasks.size() + (-(history.size())) + (-MIN_WORDS) <= 0){//If there's enough wordsif(history.size() >= MIN_WORDS){//Print the listprintBitmasks(history);}return;//To make it faster, we can stop it after 5 words too}else if(history.size() >= MAX_WORDS){//Print the listprintBitmasks(history);return;}//Thin out the array with only stuff that matches the currentBitmask.std::vector<unsigned int> newBitmasks;std::copy_if(oldBitmasks.begin(), oldBitmasks.end(), std::back_inserter(newBitmasks), [¤tBitmask](unsigned int bruh){return (bruh & currentBitmask) == 0;});while(newBitmasks.size() > 0){//I know this modifies 'oldBitmasks' too. It's intentional.//This makes it so that the word is never involved in any of the child serches or any of the later searches in this while loop.const unsigned int word = newBitmasks.back(); newBitmasks.pop_back();std::vector<unsigned int> newHistory = history;newHistory.push_back(word);recurse(newBitmasks, newHistory, currentBitmask | word);}}int main(){const std::set<unsigned int>* bitmasksSet = getBitmasks();std::vector<unsigned int> bitmasks(bitmasksSet->begin(), bitmasksSet->end());delete bitmasksSet;recurse(bitmasks, std::vector<unsigned int>(), 0);return 0;}
/*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;}
#include <string>#include <iostream>#include "PlaylistNode.h"using namespace std;PlaylistNode::PlaylistNode() {uniqueID = "none";songName = "none";artistName = "none";songLength = 0;nextNodePtr = 0;}PlaylistNode::PlaylistNode(string uniqueID_, string songName_, string artistName_, int songLength_) {uniqueID = uniqueID_;songName = songName_;artistName = artistName_;songLength = songLength_;nextNodePtr = 0;}void PlaylistNode::InsertAfter(PlaylistNode* ptr) {this->SetNext(ptr->GetNext());ptr->SetNext(this);}void PlaylistNode::SetNext(PlaylistNode* ptr) {nextNodePtr = ptr;}string PlaylistNode::GetID() {return uniqueID;}string PlaylistNode::GetSongName() {return songName;}string PlaylistNode::GetArtistName() {return artistName;}int PlaylistNode::GetSongLength() {return songLength;}PlaylistNode* PlaylistNode::GetNext() {return nextNodePtr;}void PlaylistNode::PrintPlaylistNode() {cout << "Unique ID: " << uniqueID << endl;cout << "Song Name: " << songName << endl;cout << "Artist Name: " << artistName << endl;cout << "Song Length (in seconds): " << songLength << endl;}Playlist::Playlist() {head = tail = 0;}void Playlist::AddSong(string id, string songname, string artistname, int length) {PlaylistNode* n = new PlaylistNode(id, songname, artistname, length);if (head == 0) {head = tail = n;}else {n->InsertAfter(tail);tail = n;}}bool Playlist::RemoveSong(string id) {if (head == NULL) {cout << "Playlist is empty" << endl;return false;}PlaylistNode* curr = head;PlaylistNode* prev = NULL;while (curr != NULL) {if (curr->GetID() == id) {break;}prev = curr;curr = curr->GetNext();}if (curr == NULL) {cout << "\"" << curr->GetSongName() << "\" is not found" << endl;return false;}else {if (prev != NULL) {prev ->SetNext(curr->GetNext());}else {head = curr->GetNext();}if (tail == curr) {tail = prev;}cout << "\"" << curr->GetSongName() << "\" removed." << endl;delete curr;return true;}}bool Playlist::ChangePosition(int oldPos, int newPos) {if (head == NULL) {cout << "Playlist is empty" << endl;return false;}PlaylistNode* prev = NULL;PlaylistNode* curr = head;int pos;if (head == NULL || head == tail) {return false;}for (pos = 1; curr != NULL && pos < oldPos; pos++) {prev = curr;curr = curr->GetNext();}if (curr != NULL) {string currentSong = curr->GetSongName();if (prev == NULL) {head = curr->GetNext();}else {prev->SetNext(curr->GetNext());}if (curr == tail) {tail = prev;}PlaylistNode* curr1 = curr;prev = NULL;curr = head;for (pos = 1; curr != NULL && pos < newPos; pos++) {prev = curr;curr = curr->GetNext();}if (prev == NULL) {curr1->SetNext(head);head = curr1;}else {curr1->InsertAfter(prev);}if (curr == NULL) {tail = curr1;}cout << "\"" << currentSong << "\" moved to position " << newPos << endl;return true;}else {cout << "Song's current position is invalid" << endl;return false;}}void Playlist::SongsByArtist(string artist) {if (head == NULL) {cout << "Playlist is empty" << endl;}else {PlaylistNode* curr = head;int i = 1;while (curr != NULL) {if (curr->GetArtistName() == artist) {cout << endl << i << "." << endl;curr->PrintPlaylistNode();}curr = curr->GetNext();i++;}}}int Playlist::TotalTime() {int total = 0;PlaylistNode* curr = head;while (curr != NULL) {total += curr->GetSongLength();curr = curr->GetNext();}return total;}void Playlist::PrintList() {if (head == NULL) {cout << "Playlist is empty" << endl;}else {PlaylistNode* curr = head;int i = 1;while (curr != NULL) {cout << endl << i++ << "." << endl;curr->PrintPlaylistNode();curr = curr->GetNext();}}}
using namespace std;class Hash{int BUCKET; // No. of buckets// Pointer to an array containing bucketslist<int> *table;public:Hash(int V); // Constructor// inserts a key into hash tablevoid insertItem(int x);// deletes a key from hash tablevoid deleteItem(int key);// hash function to map values to keyint hashFunction(int x) {return (x % BUCKET);}void displayHash();};Hash::Hash(int b){this->BUCKET = b;table = new list<int>[BUCKET];}void Hash::insertItem(int key){int index = hashFunction(key);table[index].push_back(key);}void Hash::deleteItem(int key){// get the hash index of keyint index = hashFunction(key);// find the key in (inex)th listlist <int> :: iterator i;for (i = table[index].begin();i != table[index].end(); i++) {if (*i == key)break;}// if key is found in hash table, remove itif (i != table[index].end())table[index].erase(i);}// function to display hash tablevoid Hash::displayHash() {for (int i = 0; i < BUCKET; i++) {cout << i;for (auto x : table[i])cout << " --> " << x;cout << endl;}}// Driver programint main(){// array that contains keys to be mappedint a[] = {15, 11, 27, 8, 12};int n = sizeof(a)/sizeof(a[0]);// insert the keys into the hash tableHash h(7); // 7 is count of buckets in// hash tablefor (int i = 0; i < n; i++)h.insertItem(a[i]);// delete 12 from hash tableh.deleteItem(12);// display the Hash tableh.displayHash();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);}