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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;}
/*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;}
#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;int main() {cout << "Hello World!\n";// Prints out "Hello World"return 0;}
//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;}
//Leif Messinger//Compile with C++ 20#include <iostream>#include <ranges>#include <vector>#include <functional>#include <cctype> //toupper#include <cxxabi.h>template <typename T>void printType(){std::cout << abi::__cxa_demangle(typeid(T).name(), NULL, NULL, NULL) << std::endl;}template <typename T>class Slicer{public:T begin_;T end_;T trueEnd;Slicer(T begin, T end): begin_(begin), end_(begin), trueEnd(end){}template<typename U>Slicer(U&& vec) : begin_(vec.begin()), end_(vec.begin()), trueEnd(vec.end()){}Slicer& finish(){begin_ = end_;end_ = trueEnd;return (*this);}Slicer& to(long int index){begin_ = end_;if(index > 0){end_ = (begin_ + index);}else{index *= -1;end_ = (trueEnd - index);}return (*this);}Slicer& operator[](long int index){return to(index);}T begin(){return this->begin_;}T end(){return this->end_;}Slicer& operator()(std::function<void(decltype(*begin_))> func) {for(decltype(*begin_) thing : (*this)){func(thing);}return (*this);}};static_assert(std::ranges::range< Slicer<std::vector<int>::const_iterator> >);int main(){std::string vec = "abcdefghijklmnopqrstuvwxyz";Slicer<std::string::const_iterator> bruh(vec);//printType<decltype(bruh)>();bruh.to(3)([](char yeet){std::cout << yeet;}).to(-1)([](char yeet){std::cout << char(std::toupper(yeet));}).finish()([](char yeet){std::cout << yeet << yeet << yeet << yeet << yeet;});std::cout << std::endl << std::endl;int arr[] = {1, 2, 3, 4, 5, 6, 7, 8};Slicer<int*> arrSlicer(arr, arr + (sizeof(arr)/sizeof(int)));std::cout << "[";arrSlicer.to(-1)([](int yeet){std::cout << yeet << ", ";}).finish()([](int yeet){std::cout << yeet << "]" << std::endl;});return 0;}