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set hostname syscall

Oct 7, 2023AustinLeath
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C++ Scanner

Jul 16, 2024LeifMessinger

0 likes • 12 views

//===============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 debugging
bool fillBuffer();
bool bufferEmpty();
void printBufferEmpty();
std::string getBuffer();
size_t bufferLength();
void printBufferStats();
//Int
bool hasNextInt();
int nextInt();
//Word
bool hasNextWord();
std::string nextWord();
//Line
bool hasNextLine();
//Whitespace
size_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 read
size_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 filled
return "";
}
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;
}

Compute Volume of Cylinder

Nov 18, 2022AustinLeath

0 likes • 0 views

/*
Algorithm:
Step 1: Get radius of the cylinder from the user and store in variable r
Step 2: Get height of the cylinder from the user and store in variable h
Step 3: Multiply radius * radius * height * pi and store in v
Step 4: Display the volume
*/
#include <iostream>
using namespace std;
int main()
{
float r; //define variable for radius
float h; //define variable for height
float v;
float pi;
pi=3.1416;
cout<<"Enter radius:";
cin>>r;
cout<<"Enter height:";
cin>>h;
v=r*r*h*pi; //compute volume
cout<<"Radius:"<<r<<"\tHeight:"<<h<<endl; //display radius and height
cout<<"\n************************\n";
cout<<"Volume:"<<v<<endl;//display volume
return 0;
}

SAM 5 words with bitmaps

Oct 23, 2022LeifMessinger

0 likes • 1 view

//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 deleted
const 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 left
if(oldBitmasks.size() + (-(history.size())) + (-MIN_WORDS) <= 0){
//If there's enough words
if(history.size() >= MIN_WORDS){
//Print the list
printBitmasks(history);
}
return;
//To make it faster, we can stop it after 5 words too
}else if(history.size() >= MAX_WORDS){
//Print the list
printBitmasks(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), [&currentBitmask](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;
}

C++ SigFigs

Sep 7, 2022LeifMessinger

0 likes • 0 views

#include <iostream>
#include <cstring>
int main(int argc, char** argv){
//With decimal
if(strstr(argv[1], ".") != nullptr){
int i = 0;
//Skip i to first non 0 digit
while(argv[1][i] < '1' || argv[1][i] > '9') ++i;
//If digit comes before decimal
if((argv[1] + i) < strstr(argv[1], ".")){ //Good example of pointer arithmetic
std::cout << strlen(argv[1] + i) - 1 << std::endl; //Another good example
}else{
//If digit is after decimal
std::cout << strlen(argv[1] + i) << std::endl;
}
}else{
//Without decimal
int m = 0;
int i = 0;
while(argv[1][i] < '1' || argv[1][i] > '9') ++i; //In case of some number like 0045
for(; argv[1][i] != '\0'; ++i){
if(argv[1][i] >= '1' && argv[1][i] <= '9') m = i + 1;
}
std::cout << m << std::endl;
}
return 0;
}

Command line game

Nov 19, 2022CodeCatch

0 likes • 1 view

#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 Dimensions
int nMapHeight = 16;
float fPlayerX = 14.7f; // Player Start Position
float fPlayerY = 5.09f;
float fPlayerA = 0.0f; // Player Start Rotation
float fFOV = 3.14159f / 4.0f; // Field of View
float fDepth = 16.0f; // Maximum rendering distance
float fSpeed = 5.0f; // Walking Speed
int main()
{
// Create Screen Buffer
wchar_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, . = space
wstring 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-deterministic
tp2 = chrono::system_clock::now();
chrono::duration<float> elapsedTime = tp2 - tp1;
tp1 = tp2;
float fElapsedTime = elapsedTime.count();
// Handle CCW Rotation
if (GetAsyncKeyState((unsigned short)'A') & 0x8000)
fPlayerA -= (fSpeed * 0.75f) * fElapsedTime;
// Handle CW Rotation
if (GetAsyncKeyState((unsigned short)'D') & 0x8000)
fPlayerA += (fSpeed * 0.75f) * fElapsedTime;
// Handle Forwards movement & collision
if (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 & collision
if (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 space
float fRayAngle = (fPlayerA - fFOV/2.0f) + ((float)x / (float)nScreenWidth) * fFOV;
// Find distance to wall
float fStepSize = 0.1f; // Increment size for ray casting, decrease to increase
float fDistanceToWall = 0.0f; // resolution
bool bHitWall = false; // Set when ray hits wall block
bool bBoundary = false; // Set when ray hits boundary between two wall blocks
float fEyeX = sinf(fRayAngle); // Unit vector for ray in player space
float fEyeY = cosf(fRayAngle);
// Incrementally cast ray from player, along ray angle, testing for
// intersection with a block
while (!bHitWall && fDistanceToWall < fDepth)
{
fDistanceToWall += fStepSize;
int nTestX = (int)(fPlayerX + fEyeX * fDistanceToWall);
int nTestY = (int)(fPlayerY + fEyeY * fDistanceToWall);
// Test if ray is out of bounds
if (nTestX < 0 || nTestX >= nMapWidth || nTestY < 0 || nTestY >= nMapHeight)
{
bHitWall = true; // Just set distance to maximum depth
fDistanceToWall = fDepth;
}
else
{
// Ray is inbounds so test to see if the ray cell is a wall block
if (map.c_str()[nTestX * nMapWidth + nTestY] == '#')
{
// Ray has hit wall
bHitWall = 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 walls
vector<pair<float, float>> p;
// Test each corner of hit tile, storing the distance from
// the player, and the calculated dot product of the two rays
for (int tx = 0; tx < 2; tx++)
for (int ty = 0; ty < 2; ty++)
{
// Angle of corner to eye
float 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 farthest
sort(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 floor
int nCeiling = (float)(nScreenHeight/2.0) - nScreenHeight / ((float)fDistanceToWall);
int nFloor = nScreenHeight - nCeiling;
// Shader walls based on distance
short nShade = ' ';
if (fDistanceToWall <= fDepth / 4.0f) nShade = 0x2588; // Very close
else 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 away
if (bBoundary) nShade = ' '; // Black it out
for (int y = 0; y < nScreenHeight; y++)
{
// Each Row
if(y <= nCeiling)
screen[y*nScreenWidth + x] = ' ';
else if(y > nCeiling && y <= nFloor)
screen[y*nScreenWidth + x] = nShade;
else // Floor
{
// Shade floor based on distance
float 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 Stats
swprintf_s(screen, 40, L"X=%3.2f, Y=%3.2f, A=%3.2f FPS=%3.2f ", fPlayerX, fPlayerY, fPlayerA, 1.0f/fElapsedTime);
// Display Map
for (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 Frame
screen[nScreenWidth * nScreenHeight - 1] = '\0';
WriteConsoleOutputCharacter(hConsole, screen, nScreenWidth * nScreenHeight, { 0,0 }, &dwBytesWritten);
}
return 0;
}

Simple Greedy sort C++

Jun 30, 2023Iceman_71

0 likes • 7 views

#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;
}