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#include <iostream>#include <cstring>#include <unistd.h>#include <sys/utsname.h>int main() {char newHostname[] = "newhostname"; // Replace with the desired hostnameif (sethostname(newHostname, strlen(newHostname)) == 0) {std::cout << "Hostname set to: " << newHostname << std::endl;// Optionally, update the /etc/hostname file to make the change permanentFILE *hostnameFile = fopen("/etc/hostname", "w");if (hostnameFile != NULL) {fprintf(hostnameFile, "%s\n", newHostname);fclose(hostnameFile);} else {perror("Failed to update /etc/hostname");}} else {perror("Failed to set hostname");}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;}
#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;}
/*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;}
/*this program will simulate the spreading of a disease through agrid of people, starting from a user-defined person. It will countthe number of turns taken before everyone on the grid is immunizedto the disease after having caught it once.This program will user the SIR model (Susceptible, Infectious, Recovered)and cellular automata to simulate the people in the grid.*/#include <iostream>using namespace std;/* Any and all global variables */const int SIZE = 8; //Size of the square person array/* Any and all functions */void gridDefaultify(char[][SIZE], int);//Purpose: Sets each item in the person array to 's'//Parameters: A square, two-dimensional array// The size of that array's boundsvoid gridDisplay(char[][SIZE], int);//Purpose: Formats and prints the information in the person grid//Parameters: A square, two-dimensional array// The value of the current dayvoid nextTurn(char[][SIZE], char[][SIZE], int&);//Purpose: Updates the grid of people, and the current day//Parameters: Two square, two-dimensional arrays// A reference to the current day (so that it can be updated)int countInfected(char[][SIZE], int);//Purpose: Counts the number of infectious people on the grid//Parameters: A square, two-dimensional array// The size of that array's boundsint main(){int currentDay = 0; //Infection begins on day 0, and ends one day after the last person is Recoveredchar gridCurrent[SIZE][SIZE]; //Grid of all peoplechar gridUpdate[SIZE][SIZE]; //Where the user chooses to start the infectionint xToInfect;int yToInfect; //Set of coordinates for the initial infection position, given by user//Initializes the grids to all 's'gridDefaultify(gridCurrent, SIZE);gridDefaultify(gridUpdate, SIZE);//The below block gets the initial infection coordinates from the usercout << "Please enter a location to infect: ";while(true){cin >> xToInfect >> yToInfect;xToInfect--;yToInfect--;if(xToInfect < 0 || yToInfect < 0 || xToInfect >= SIZE || yToInfect >= SIZE){cout << "Those coordinates are outside the bounds of this region." << endl;cout << "Please enter another location to infect: ";continue;} else {gridCurrent[xToInfect][yToInfect] = 'i';break;}}//Displays the initial state of the gridgridDisplay(gridCurrent, currentDay);//The below block will display and update the grid until the infection is done.while(true){nextTurn(gridCurrent, gridUpdate, currentDay);gridDisplay(gridCurrent, currentDay);if(countInfected(gridCurrent, SIZE) == 0) break; //Once there are no more infected, the game is done}//Displays the number of days taken for the infection to endcout << "It took " << currentDay + 1 << " days for the outbreak to end";cout << endl;return 0;}void gridDefaultify(char arr[][SIZE], int arrSize){for(int x = 0; x < arrSize; x++){for(int y = 0; y < arrSize; y++){arr[x][y] = 's'; //Sets all items in the passed-in array to 's'}}return;}void gridDisplay(char arr[][SIZE], int day){cout << "Day " << day << endl; //Prints the current dayfor(int x = 0; x < SIZE; x++){for(int y = 0; y < SIZE; y++){cout << arr[x][y] <<" "; //Prints the array's contents}cout << endl; //Formats with newlines}cout << endl; //Some spacingreturn;}void nextTurn(char today[][SIZE], char update[][SIZE], int& day){day++; //Updates the dayint xCheck; //X coordinate to be checkedint yCheck; //Y coordinate to be checkedfor(int x = 0; x < SIZE; x++){for(int y = 0; y < SIZE; y++){//Sets all 'i' to 'r' in the new gridif(today[x][y] == 'i' || today[x][y] == 'r'){update[x][y] = 'r'; //Updates all infectious to recovered, and keeps current recovered}if(today[x][y] == 's'){ // If the person is susceptible...for(int xCheck = x-1; xCheck <= x+1; xCheck++){ // Check all x coordinates around the personfor(int yCheck = y-1; yCheck <= y+1; yCheck++){ // Check all y coordinates around the personif(xCheck == x && yCheck == y){// Don't check at the person because there is no need to check there} else {if(xCheck >= 0 && yCheck >= 0 && xCheck < SIZE && yCheck < SIZE){ // Make sure the checked coordinates are in boundsif(today[xCheck][yCheck] == 'i'){ //Is the person at the checked coordinates infected?update[x][y] = 'i'; //If so, update the 's' to 'i' in the new grid}}}}}}}}for(int x = 0; x < SIZE; x++){for(int y = 0; y < SIZE; y++){today[x][y] = update[x][y]; //Updates today's grid with the new values}}}int countInfected(char arr[][SIZE], int arrSize){int count = 0;for(int x = 0; x < arrSize; x++){for(int y = 0; y < arrSize; y++){if(arr[x][y] == 'i') count++; //Increments count for each infected person in the grid}}return count;}
//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;}