using namespace std; 
  
class Hash 
{ 
    int BUCKET;    // No. of buckets 
  
    // Pointer to an array containing buckets 
    list<int> *table; 
public: 
    Hash(int V);  // Constructor 
  
    // inserts a key into hash table 
    void insertItem(int x); 
  
    // deletes a key from hash table 
    void deleteItem(int key); 
  
    // hash function to map values to key 
    int hashFunction(int x) { 
        return (x % BUCKET); 
    } 
  
    void displayHash(); 
}; 
  
Hash::Hash(int b) 
{ 
    this->BUCKET = b; 
    table = new list<int>[BUCKET]; 
} 
  
void Hash::insertItem(int key) 
{ 
    int index = hashFunction(key); 
    table[index].push_back(key);  
} 
  
void Hash::deleteItem(int key) 
{ 
  // get the hash index of key 
  int index = hashFunction(key); 
  
  // find the key in (inex)th list 
  list <int> :: iterator i; 
  for (i = table[index].begin(); 
           i != table[index].end(); i++) { 
    if (*i == key) 
      break; 
  } 
  
  // if key is found in hash table, remove it 
  if (i != table[index].end()) 
    table[index].erase(i); 
} 
  
// function to display hash table 
void Hash::displayHash() { 
  for (int i = 0; i < BUCKET; i++) { 
    cout << i; 
    for (auto x : table[i]) 
      cout << " --> " << x; 
    cout << endl; 
  } 
} 
  
// Driver program  
int main() 
{ 
  // array that contains keys to be mapped 
  int a[] = {15, 11, 27, 8, 12}; 
  int n = sizeof(a)/sizeof(a[0]); 
  
  // insert the keys into the hash table 
  Hash h(7);   // 7 is count of buckets in 
               // hash table 
  for (int i = 0; i < n; i++)  
    h.insertItem(a[i]);   
  
  // delete 12 from hash table 
  h.deleteItem(12); 
  
  // display the Hash table 
  h.displayHash(); 
  
  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, zz

int 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;
}

#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 "goat.h" //include goat.h

void Goat::setBreed(string breed) {
   this->breed = breed;
}
void Goat::setWeight(float weight) {
   this->weight = weight;
}
void Goat::setName(string name) {
   this->name = name;
}
void Goat::setGender(char gender) {
   this->gender = gender;
}
void Goat::setSpayed(bool goatIsSpayed) {
   this->goatIsSpayed = goatIsSpayed;
}
void Goat::setRegistrationID(string registrationID) {
   this->registrationID = registrationID;
}
void Goat::setColor(string color) {
   this->color = color;
}
void Goat::setOtherComments(string otherComments) {
   this->otherComments = otherComments;
}
string Goat::getBreed() {
   return breed;
}
float Goat::getWeight() {
   return weight;
}
string Goat::getName() {
   return name;
}
char Goat::getGender() {
   return gender;
}
bool Goat::getSpayed() {
   return goatIsSpayed;
}
string Goat::getRegistrationID() {
   return registrationID;
}
string Goat::getColor() {
   return color;
}
string Goat::getOtherComments() {
   return otherComments;
}

Goat::Goat() {
   breed = "";
   weight = 0.0;
   name = "";
   gender = '\0';
   goatIsSpayed = false;
   registrationID = "";
   color = "";
   otherComments = "";
}

Goat::Goat(string goatBreed, float goatWeight, string goatName, char goatGender, bool goatSpayedStatus, string goatRegistrationID, string goatColor, string goatOtherComments) {
  
   breed = goatBreed;
   weight = goatWeight;
   name = goatName;
   gender = goatGender;
   goatIsSpayed = goatSpayedStatus;
   registrationID = goatRegistrationID;
   color = goatColor;
   otherComments = goatOtherComments;
}

Goat::~Goat() {
   cout << "goat destroyed" << endl;
}

void Goat::printinfo() {  
   cout << "Breed: " << breed << endl << "weight: " << weight << endl << "Name: " << name << endl << "Gender: " << gender << endl << "is Spayed: ";
   if(goatIsSpayed) {  //here I do a logical test on boolean goatIsSpayed. if true cout << true else cout << false
      cout << "True";
   } else {
      cout << "False";
   }
   cout << endl << "Registration ID: " << registrationID << endl << "Color Description: " << color << endl << "Other Comments: " << otherComments << endl << endl;
}

#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;
}

#include <iostream>
using namespace std;

/* Function: get_coeff
Parameters: double& coeff, int pos passed from bb_4ac
Return: type is void so no return, but does ask for user to input data that establishes what a b and c are.
*/
void get_coeff(double& coeff, int pos) {
  char position;
  if(pos == 1) {
    position = 'a';
  } else if(pos == 2) {   //a simple system to determine what coefficient the program is asking for.
    position = 'b';
  } else {
    position = 'c';
  }
  cout << "Enter the co-efficient " << position << ":"; //prompt to input coeff
  coeff = 5; //input coeff
}

/* Function: bb_4ac
Parameters: no parameters passed from main, but 3 params established in function, double a, b, c.
Return: b * b - 4 * a * c
*/
double bb_4ac() {
  double a, b, c; //coefficients of a quadratic equation
  get_coeff(a, 1); // call function 1st time
  get_coeff(b, 2); // call function 2nd time
  get_coeff(c, 3); // call function 3rd time
  return b * b - 4 * a * c; //return b * b - 4 * a * c
}

int main() {
  cout << "Function to calculate the discriminant of the equation. . . " << endl;
  double determinate = bb_4ac(); //assign double determinate to bb_4ac function
  cout << "The discriminant for given values is: " << determinate << endl;  //output the determinate!
}