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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;}
/*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 <iostream>using namespace std;int main(){int arr[] = {5, 1, 4, 20, 10, 2, 13, 11, 6, 21};int greed[] = {0, 0, 0, 0};int k = 0;int i;int set_index;while (k < 4){i = 0;while (i < 10){if (arr[i] > greed[k]){greed[k] = arr[i];set_index = i;}i++;}arr[set_index] = 0;k++;}cout << greed[0] << " " << greed[1] << " " << greed[2] << " " << greed[3] << endl;}
#include <iostream>using namespace std;int main {cout << 1;}
#include <iostream>using namespace std;int main() {cout << "Hello World!\n";// Prints out "Hello World"return 0;}
#include <iostream>#include <string> //Should already be in iostream#include <cstdlib>//A word score adds up the character values. a-z gets mapped to 1-26 for the values of the characters.//wordScore [wordValue]//Pipe in the input into stdin, or type the words yourself.//Lowercase words onlyint characterValue(const char b){return ((b >= 'a') && (b <= 'z'))? ((b - 'a') + 1) : 0;}int main(int argc, char** argv){//The first argument specifies if you are trying to look for a certain word scoreint wordValue = (argc > 1)? std::atoi(argv[1]) : 0;std::string line;while(std::getline(std::cin, line)){int sum = 0;for(const char c : line){sum += characterValue(c);}if(wordValue){ //If wordValue is 0 or the sum is the correct valueif(wordValue == sum){std::cout << line << std::endl;}} else {std::cout << sum << "\t" << line << std::endl;}}return 0;}