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#include <iostream>#include <cmath>#include <string.h>using namespace std;int main() {string tickerName;int numOfContracts;float currentOptionValue;cout << "Enter a stock ticker: ";getline(cin, tickerName);cout << "Enter the current number of " << tickerName << " contracts you are holding: ";cin >> numOfContracts;cout << "Enter the current price of the option: ";cin >> currentOptionValue;cout << "The value of your " << tickerName << " options are: $" << (currentOptionValue * 100.00) * (numOfContracts);cout << endl;return 0;}
#include <iostream>#include <cstring>int main(int argc, char** argv){//With decimalif(strstr(argv[1], ".") != nullptr){int i = 0;//Skip i to first non 0 digitwhile(argv[1][i] < '1' || argv[1][i] > '9') ++i;//If digit comes before decimalif((argv[1] + i) < strstr(argv[1], ".")){ //Good example of pointer arithmeticstd::cout << strlen(argv[1] + i) - 1 << std::endl; //Another good example}else{//If digit is after decimalstd::cout << strlen(argv[1] + i) << std::endl;}}else{//Without decimalint m = 0;int i = 0;while(argv[1][i] < '1' || argv[1][i] > '9') ++i; //In case of some number like 0045for(; argv[1][i] != '\0'; ++i){if(argv[1][i] >= '1' && argv[1][i] <= '9') m = i + 1;}std::cout << m << std::endl;}return 0;}
#include <iostream>#include <fstream>#include <string>#include <cstring>using namespace std;//This program makes a new text file that contains all combinations of two letters.// aa, ab, ..., zy, zzint main(){string filename = "two_letters.txt";ofstream outFile;outFile.open(filename.c_str());if(!outFile.is_open()){cout << "Something's wrong. Closing..." << endl;return 0;}for(char first = 'a'; first <= 'z'; first++){for(char second = 'a'; second <= 'z'; second++){outFile << first << second << " ";}outFile << endl;}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;}
//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;}
#include <iostream>#include <vector>#include <utility>#include <algorithm>#include <chrono>using namespace std;#include <stdio.h>#include <Windows.h>int nScreenWidth = 120; // Console Screen Size X (columns)int nScreenHeight = 40; // Console Screen Size Y (rows)int nMapWidth = 16; // World Dimensionsint nMapHeight = 16;float fPlayerX = 14.7f; // Player Start Positionfloat fPlayerY = 5.09f;float fPlayerA = 0.0f; // Player Start Rotationfloat fFOV = 3.14159f / 4.0f; // Field of Viewfloat fDepth = 16.0f; // Maximum rendering distancefloat fSpeed = 5.0f; // Walking Speedint main(){// Create Screen Bufferwchar_t *screen = new wchar_t[nScreenWidth*nScreenHeight];HANDLE hConsole = CreateConsoleScreenBuffer(GENERIC_READ | GENERIC_WRITE, 0, NULL, CONSOLE_TEXTMODE_BUFFER, NULL);SetConsoleActiveScreenBuffer(hConsole);DWORD dwBytesWritten = 0;// Create Map of world space # = wall block, . = spacewstring map;map += L"#########.......";map += L"#...............";map += L"#.......########";map += L"#..............#";map += L"#......##......#";map += L"#......##......#";map += L"#..............#";map += L"###............#";map += L"##.............#";map += L"#......####..###";map += L"#......#.......#";map += L"#......#.......#";map += L"#..............#";map += L"#......#########";map += L"#..............#";map += L"################";auto tp1 = chrono::system_clock::now();auto tp2 = chrono::system_clock::now();while (1){// We'll need time differential per frame to calculate modification// to movement speeds, to ensure consistant movement, as ray-tracing// is non-deterministictp2 = chrono::system_clock::now();chrono::duration<float> elapsedTime = tp2 - tp1;tp1 = tp2;float fElapsedTime = elapsedTime.count();// Handle CCW Rotationif (GetAsyncKeyState((unsigned short)'A') & 0x8000)fPlayerA -= (fSpeed * 0.75f) * fElapsedTime;// Handle CW Rotationif (GetAsyncKeyState((unsigned short)'D') & 0x8000)fPlayerA += (fSpeed * 0.75f) * fElapsedTime;// Handle Forwards movement & collisionif (GetAsyncKeyState((unsigned short)'W') & 0x8000){fPlayerX += sinf(fPlayerA) * fSpeed * fElapsedTime;;fPlayerY += cosf(fPlayerA) * fSpeed * fElapsedTime;;if (map.c_str()[(int)fPlayerX * nMapWidth + (int)fPlayerY] == '#'){fPlayerX -= sinf(fPlayerA) * fSpeed * fElapsedTime;;fPlayerY -= cosf(fPlayerA) * fSpeed * fElapsedTime;;}}// Handle backwards movement & collisionif (GetAsyncKeyState((unsigned short)'S') & 0x8000){fPlayerX -= sinf(fPlayerA) * fSpeed * fElapsedTime;;fPlayerY -= cosf(fPlayerA) * fSpeed * fElapsedTime;;if (map.c_str()[(int)fPlayerX * nMapWidth + (int)fPlayerY] == '#'){fPlayerX += sinf(fPlayerA) * fSpeed * fElapsedTime;;fPlayerY += cosf(fPlayerA) * fSpeed * fElapsedTime;;}}for (int x = 0; x < nScreenWidth; x++){// For each column, calculate the projected ray angle into world spacefloat fRayAngle = (fPlayerA - fFOV/2.0f) + ((float)x / (float)nScreenWidth) * fFOV;// Find distance to wallfloat fStepSize = 0.1f; // Increment size for ray casting, decrease to increasefloat fDistanceToWall = 0.0f; // resolutionbool bHitWall = false; // Set when ray hits wall blockbool bBoundary = false; // Set when ray hits boundary between two wall blocksfloat fEyeX = sinf(fRayAngle); // Unit vector for ray in player spacefloat fEyeY = cosf(fRayAngle);// Incrementally cast ray from player, along ray angle, testing for// intersection with a blockwhile (!bHitWall && fDistanceToWall < fDepth){fDistanceToWall += fStepSize;int nTestX = (int)(fPlayerX + fEyeX * fDistanceToWall);int nTestY = (int)(fPlayerY + fEyeY * fDistanceToWall);// Test if ray is out of boundsif (nTestX < 0 || nTestX >= nMapWidth || nTestY < 0 || nTestY >= nMapHeight){bHitWall = true; // Just set distance to maximum depthfDistanceToWall = fDepth;}else{// Ray is inbounds so test to see if the ray cell is a wall blockif (map.c_str()[nTestX * nMapWidth + nTestY] == '#'){// Ray has hit wallbHitWall = true;// To highlight tile boundaries, cast a ray from each corner// of the tile, to the player. The more coincident this ray// is to the rendering ray, the closer we are to a tile// boundary, which we'll shade to add detail to the wallsvector<pair<float, float>> p;// Test each corner of hit tile, storing the distance from// the player, and the calculated dot product of the two raysfor (int tx = 0; tx < 2; tx++)for (int ty = 0; ty < 2; ty++){// Angle of corner to eyefloat vy = (float)nTestY + ty - fPlayerY;float vx = (float)nTestX + tx - fPlayerX;float d = sqrt(vx*vx + vy*vy);float dot = (fEyeX * vx / d) + (fEyeY * vy / d);p.push_back(make_pair(d, dot));}// Sort Pairs from closest to farthestsort(p.begin(), p.end(), [](const pair<float, float> &left, const pair<float, float> &right) {return left.first < right.first; });// First two/three are closest (we will never see all four)float fBound = 0.01;if (acos(p.at(0).second) < fBound) bBoundary = true;if (acos(p.at(1).second) < fBound) bBoundary = true;if (acos(p.at(2).second) < fBound) bBoundary = true;}}}// Calculate distance to ceiling and floorint nCeiling = (float)(nScreenHeight/2.0) - nScreenHeight / ((float)fDistanceToWall);int nFloor = nScreenHeight - nCeiling;// Shader walls based on distanceshort nShade = ' ';if (fDistanceToWall <= fDepth / 4.0f) nShade = 0x2588; // Very closeelse if (fDistanceToWall < fDepth / 3.0f) nShade = 0x2593;else if (fDistanceToWall < fDepth / 2.0f) nShade = 0x2592;else if (fDistanceToWall < fDepth) nShade = 0x2591;else nShade = ' '; // Too far awayif (bBoundary) nShade = ' '; // Black it outfor (int y = 0; y < nScreenHeight; y++){// Each Rowif(y <= nCeiling)screen[y*nScreenWidth + x] = ' ';else if(y > nCeiling && y <= nFloor)screen[y*nScreenWidth + x] = nShade;else // Floor{// Shade floor based on distancefloat b = 1.0f - (((float)y -nScreenHeight/2.0f) / ((float)nScreenHeight / 2.0f));if (b < 0.25) nShade = '#';else if (b < 0.5) nShade = 'x';else if (b < 0.75) nShade = '.';else if (b < 0.9) nShade = '-';else nShade = ' ';screen[y*nScreenWidth + x] = nShade;}}}// Display Statsswprintf_s(screen, 40, L"X=%3.2f, Y=%3.2f, A=%3.2f FPS=%3.2f ", fPlayerX, fPlayerY, fPlayerA, 1.0f/fElapsedTime);// Display Mapfor (int nx = 0; nx < nMapWidth; nx++)for (int ny = 0; ny < nMapWidth; ny++){screen[(ny+1)*nScreenWidth + nx] = map[ny * nMapWidth + nx];}screen[((int)fPlayerX+1) * nScreenWidth + (int)fPlayerY] = 'P';// Display Framescreen[nScreenWidth * nScreenHeight - 1] = '\0';WriteConsoleOutputCharacter(hConsole, screen, nScreenWidth * nScreenHeight, { 0,0 }, &dwBytesWritten);}return 0;}