//===============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;
}

// Iterative C++ program to
// implement Stein's Algorithm
//#include <bits/stdc++.h>
#include <bitset>
using namespace std;

// Function to implement
// Stein's Algorithm
int gcd(int a, int b)
{
    /* GCD(0, b) == b; GCD(a, 0) == a,
    GCD(0, 0) == 0 */
    if (a == 0)
        return b;
    if (b == 0)
        return a;

    /*Finding K, where K is the
    greatest power of 2
    that divides both a and b. */
    int k;
    for (k = 0; ((a | b) & 1) == 0; ++k)
    {
        a >>= 1;
        b >>= 1;
    }

    /* Dividing a by 2 until a becomes odd */
    while ((a & 1) == 0)
        a >>= 1;

    /* From here on, 'a' is always odd. */
    do
    {
        /* If b is even, remove all factor of 2 in b */
        while ((b & 1) == 0)
            b >>= 1;

        /* Now a and b are both odd.
        Swap if necessary so a <= b,
        then set b = b - a (which is even).*/
        if (a > b)
            swap(a, b); // Swap u and v.

        b = (b - a);
    } while (b != 0);

    /* restore common factors of 2 */
    return a << k;
}

// Driver code
int main()
{
    int a = 12, b = 780;
    printf("Gcd of given numbers is %d\n", gcd(a, b));
    return 0;
}

#include <iostream>
#include "PlaylistNode.h"
using namespace std;
void PrintMenu(string title);

int main() {
   string plTitle;
   cout << "Enter playlist's title:" << endl;
   getline(cin, plTitle);
   PrintMenu(plTitle);
   return 0;
}

void PrintMenu(string title) {
   Playlist list;
   string id;
   string sname;
   string aname;
   int length;
   int oldPos;
   int newPos;
   char choice;
   
   while(true) {
      cout << endl << title << " PLAYLIST MENU" << endl;
      cout << "a - Add song" << endl;
      cout << "d - Remove song" << endl;
      cout << "c - Change position of song" << endl;
      cout << "s - Output songs by specific artist" << endl;
      cout << "t - Output total time of playlist (in seconds)" << endl;
      cout << "o - Output full playlist" << endl;
      cout << "q - Quit" << endl << endl;
      
      cout << "Choose an option:" << endl;
      cin >> choice;
      cin.ignore();
      
      if (choice == 'q') {
         exit(1);
      }
      else if (choice == 'a') {
         cout << "\nADD SONG" << endl;
         cout << "Enter song's unique ID: ";
         cin >> id;
         cin.ignore();
         cout << "Enter song's name: ";
         getline(cin,sname);
         cout << "Enter artist's name: ";
         getline(cin,aname);
         cout << "Enter song's length (in seconds): ";
         cin >> length;
         list.AddSong(id, sname, aname, length);
      }
      else if (choice == 'd') {
         cout << "\nREMOVE SONG" << endl;
         cout << "Enter song's unique ID: ";
         cin >> id;
         list.RemoveSong(id);
      }
      else if (choice == 'c') {
         cout << "\nCHANGE POSITION OF SONG" << endl;
         cout << "Enter song's current position: ";
         cin >> oldPos;
         cout << "Enter new position for song: ";
         cin >> newPos;
         list.ChangePosition(oldPos, newPos);
      }
      else if (choice == 's') {
         cout << "\nOUTPUT SONGS BY SPECIFIC ARTIST" << endl;
         cout << "Enter artist's name: ";
         getline(cin, aname);
         list.SongsByArtist(aname);
      }
      else if (choice == 't') {
         cout << "\nOUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)" << endl;
         cout << "Total time: " << list.TotalTime() << " seconds" << endl;
      }
      else if (choice == 'o') {
         cout << endl << title << " - OUTPUT FULL PLAYLIST" << endl;
         list.PrintList();
      }
      else {
         cout << "Invalid menu choice! Please try again." << endl;
      }
   }
}

#include <bits/stdc++.h>
#define MAXSIZE 50000
#define INF 100000

using namespace std;

vector<int> adj[MAXSIZE]; //Adjacency List

bool visited[MAXSIZE]; //Checks if a node is visited or not in BFS and DFS
bool isConnected = true; //Checks if the input graph is connected or not

int dist[MAXSIZE], discover[MAXSIZE], finish[MAXSIZE]; //Distance for BFS, in time and out time for DFS
int t = 1; //Time used for DFS
int u, v, i, j, k, N = 0;

stack<int> st; //Stack for TopSort

multiset<pair<int, int>> s; //collection of pairs to sort by distance
pair<int, int> current; //pointer variable to a position in the multiset

void BFS()
{
	queue<int> q; //queue for BFS
	q.push(1); //pushing the source
	dist[1] = 0; //assign the distance of source as 0
	visited[1] = 1; //marking as visited
	
	while(!q.empty())
	{
	u = q.front();
	q.pop();

	for(i=0; i < adj[u].size(); i++)
	{
	v = adj[u][i]; //Adjacent vertex

	if(!visited[v]) //if not visited, update the distance and push onto queue
	{
	visited[v] = 1;
	dist[v] = dist[u]+1;
	q.push(v);
	}

	}

	}
	
	for(i = 1; i <= N; i++)
	{
	s.insert(make_pair(dist[i], i)); //for sorted distance
	}
	
	cout << "BFS results:" << endl;
	
	//prints BFS results and checks if the graph is connected
	while(!s.empty())
	{
	current = *s.begin(); 
	s.erase(s.begin());

	i = current.second; 
	j = current.first;

	if(j == INF) //if any infinite value, graph is not connected
	{
	cout << i << " INF" << endl;
	isConnected = false;
	}
	else
	{
	cout << i << " " << j << endl;
	}

	}

	//marks blocks of memory as visited
	memset(visited, 0, sizeof visited);
}


void dfsSearch(int s)
{
	visited[s] = 1; //marking it visited
	discover[s] = t++; //assigning and incrementing time

	int i, v;

	for(i = 0; i < adj[s].size(); i++)
	{
	v = adj[s][i];

	if(!visited[v]) //if vertex is not visited then visit, else continue
	{
	dfsSearch(v);
	}

	}

	st.push(s); //pushed onto stack for TopSort if it was called
	finish[s] = t++; //out time
}

void DFS()
{

	for(i = 1; i <= N; i++)
	{
	if(visited[i]) //if visited continue, else visit it with DFS
	{
	continue;
	}

	dfsSearch(i); //embedded function to actually perform DFS
	}

	for(i=1;i<=N;i++)
	{
	s.insert(make_pair(discover[i], i)); //minheap for sorted discovery time
	}
	
	cout << "DFS results:" << endl;

	while(!s.empty()) //Prints DFS results as long as the multiset is not empty
	{
	current = *s.begin(); //duplicates the pointer to first object in the multiset
	s.erase(s.begin()); //erases the first object in multiset

	i = current.second;
	cout << i << " " << discover[i] << " " << finish[i] << endl; //prints discover times and finish times
	}

}

void TopSort()
{
	//call DFS so we can have a sorted stack to print
	for(i=1;i<=N;i++)
	{
	if(visited[i])
	{
	continue;
	}

	dfsSearch(i);
	}

	cout<<"Topological Sort results:"<<endl;

	//print sorted results from DFS
	while(!st.empty())
	{
	i = st.top(); 
	st.pop();

	cout << i << endl;
	}

	//declare blocks of memory as visited
	memset(visited, 0, sizeof visited);

}


int main()
{
	string str, num, input;
	int selection, connectedChoice = 0;


	//get to input any file, more freedom than declaring file in command line
	cout << "Enter the exact name of your input file [case sensitive]: ";
	cin >> input;
	
	ifstream inputFile(input); //Read the input file

	//checks if the ifstream cannot open
	if(inputFile.fail())
	{
	cout << endl << "No input files matching that name. Terminating..." << endl;
	return 0;
	}

	//Read until the end of file
	while(!inputFile.eof())
	{
	getline(inputFile, str); //read the current line

	if(str == "")
	{
	continue;
	}

	if(!isdigit(str[0])) //checks to see if the first item in a line is a digit or not
	{
	cout << "Invalid file format. You have a line beginning with a non-digit. Terminating..." << endl;
	return 0;
	}

	stringstream ss;
	ss << str; //convert the line to stream of strings
	
	ss >> num; //read the line num
	stringstream(num) >> u;
	
	while(!ss.eof())
	{
	ss>>num;
	if(stringstream(num) >> v)
	{
	adj[u].push_back(v); //read the adjacent vertices
	}
	}

	N++; //calculate the number of vertices
	sort(adj[u].begin(), adj[u].end()); //sort the adjacency list in case it is not sorted
	}
	
	//creates arbitrary values for distance, will check later if INF remain
	for(i = 1; i <= N; i++)
	{
	dist[i] = INF;
	}

	cout << endl << "Valid Input file loaded!" << endl;

	while(selection != 4)
	{
	cout << "************************************************" << endl;
	cout << "What type of analysis would you like to perform?" << endl;
	cout << "1: Breadth-First Search" << endl;
	cout << "2: Depth-First Search" << endl;
	cout << "3: Topological Sort" << endl;
	cout << "4: Quit" << endl;
	cout << "************************************************" << endl;
	
	//read user input and execute selection
	cin >> selection;

	switch(selection)
	{
	case 1:
	cout << endl;
	BFS();
	cout << endl;
	cout << "Would you like to know if the graph is connected?" << endl;
	cout << "1: Yes" << endl;
	cout << "Any other key: No" << endl;
	cin >> connectedChoice;

	switch(connectedChoice)
	{
	case 1:
	if(!isConnected)
	{
	cout << "The graph is not connected." << endl << endl;
	}
	else
	{
	cout << "The graph is connected!" << endl << endl;
	}
	break;
	default:
	break;
	}
	break;
	case 2:
	cout << endl;
	DFS();
	cout << endl;
	break;
	case 3:
	cout << endl;
	TopSort();
	cout << endl;
	break;
	case 4:
	return 0;
	default:
	cout << endl << "Invalid selection." << endl; //loops the selection prompt until a valid selection is input.
	}

	}
	
}

#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 <iostream>
int main(){
    const char* const hello = "Hello, world!";
    
    const char* bruh = hello;
    
    char* const yeet = hello;
    
    std::cout << bruh << std::endl;
    
    std::cout << yeet << std::endl;
    
    return 0;
}

/*
    Place your bets!
    
    Will the program:
    a.) Print "Hello, world!" twice?
    b.) Compile error on line 5 (bruh initialize line) because the pointer gets implicit cast to non-const?
    c.) Compile error on line 7 (yeet initialize line) because the char gets implicit cast to non-const?
    d.) Both b and c?
    e.) Compile error line 11 (print yeet) because the pointer is constant and can't be incremented
    f.) Print "Hello, world!" then print the pointer address in hexadecimal
    g.) Both b and e?
    h.) Both c and e?
    i.) B, c, and e?
    
*/

// The answer is in this base 64 string:
// 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