#include "stdio.h"
#include <stdlib.h>

int main (int argCount, char** args) {
    int a = atoi(args[1]);
    int b = atoi(args[2]);

    unsigned int sum = 0;

    unsigned int p = 1;
    for (unsigned int i = 1; i < b; i++) {
        p = p * i;
    }

    // (b!, (1 + b)!, (2 + b)!, ..., (n + b)!)
    for (unsigned int i = 0; i < a; i++) {
        p = p * (i + b);
        sum = sum + p;
    }
    printf("y: %u\n", sum);
    return 0;
}

#include <string>
#include <iostream>
#include "PlaylistNode.h"
using namespace std;

PlaylistNode::PlaylistNode() {
   uniqueID = "none";
   songName = "none";
   artistName = "none";
   songLength = 0;
   nextNodePtr = 0;
}

PlaylistNode::PlaylistNode(string uniqueID_, string songName_, string artistName_, int songLength_) {
   uniqueID = uniqueID_;
   songName = songName_;
   artistName = artistName_;
   songLength = songLength_;
   nextNodePtr = 0;
}

void PlaylistNode::InsertAfter(PlaylistNode* ptr) {
   this->SetNext(ptr->GetNext());
   ptr->SetNext(this);
}

void PlaylistNode::SetNext(PlaylistNode* ptr) {
   nextNodePtr = ptr;
}

string PlaylistNode::GetID() {
   return uniqueID;
}

string PlaylistNode::GetSongName() {
   return songName;
}

string PlaylistNode::GetArtistName() {
   return artistName;
}

int PlaylistNode::GetSongLength() {
   return songLength;
}

PlaylistNode* PlaylistNode::GetNext() {
   return nextNodePtr;
}

void PlaylistNode::PrintPlaylistNode() {
   cout << "Unique ID: " << uniqueID << endl;
   cout << "Song Name: " << songName << endl;
   cout << "Artist Name: " << artistName << endl;
   cout << "Song Length (in seconds): " << songLength << endl;
}

Playlist::Playlist() {
   head = tail = 0;
}

void Playlist::AddSong(string id, string songname, string artistname, int length) {
   PlaylistNode* n = new PlaylistNode(id, songname, artistname, length);
   if (head == 0) {
      head = tail = n;
   }
   else {
      n->InsertAfter(tail);
      tail = n;
   }
}

bool Playlist::RemoveSong(string id) {
   if (head == NULL) {
      cout << "Playlist is empty" << endl;
      return false;
   }
   
   PlaylistNode* curr = head;
   PlaylistNode* prev = NULL;
   while (curr != NULL) {
      if (curr->GetID() == id) {
         break;
      }
      prev = curr;
      curr = curr->GetNext();
   }
   
   if (curr == NULL) {
      cout << "\"" << curr->GetSongName() << "\" is not found" << endl;
      return false;
   }
   else {
      if (prev != NULL) {
         prev ->SetNext(curr->GetNext());
      }
      else {
         head = curr->GetNext();
      }
      if (tail == curr) {
         tail = prev;
      }
      cout << "\"" << curr->GetSongName() << "\" removed." << endl;
      delete curr;
      return true;
   }
}

bool Playlist::ChangePosition(int oldPos, int newPos) {
   if (head == NULL) {
      cout << "Playlist is empty" << endl;
      return false;
   }
   
   PlaylistNode* prev = NULL;
   PlaylistNode* curr = head;
   
   int pos;
   if (head == NULL || head == tail) {
      return false;
   }
   
   for (pos = 1; curr != NULL && pos < oldPos; pos++) {
      prev = curr;
      curr = curr->GetNext();
   }
   if (curr != NULL) {
      string currentSong = curr->GetSongName();
      
      if (prev == NULL) {
         head = curr->GetNext();
      }
      else {
         prev->SetNext(curr->GetNext());
      }
      if (curr == tail) {
         tail = prev;
      }
      
      PlaylistNode* curr1 = curr;
      prev = NULL;
      curr = head;
      for (pos = 1; curr != NULL && pos < newPos; pos++) {
         prev = curr;
         curr = curr->GetNext();
      }
      if (prev == NULL) {
         curr1->SetNext(head);
         head = curr1;
      }
      else {
         curr1->InsertAfter(prev);
      }
      if (curr == NULL) {
         tail = curr1;
      }
      cout << "\"" << currentSong << "\" moved to position " << newPos << endl;
      return true;
   }
   else {
      cout << "Song's current position is invalid" << endl;
      return false;
   }
}

void Playlist::SongsByArtist(string artist) {
   if (head == NULL) {
      cout << "Playlist is empty" << endl;
   }
   else {
      PlaylistNode* curr = head;
      int i = 1;
      while (curr != NULL) {
         if (curr->GetArtistName() == artist) {
            cout << endl << i << "." << endl;
            curr->PrintPlaylistNode();
         }
         curr = curr->GetNext();
         i++;
      }
   }
}

int Playlist::TotalTime() {
   int total = 0;
   PlaylistNode* curr = head;
   
   while (curr != NULL) {
      total += curr->GetSongLength();
      curr = curr->GetNext();
   }
   return total;
}

void Playlist::PrintList() {
   if (head == NULL) {
      cout << "Playlist is empty" << endl;
   }
   else {
      PlaylistNode* curr = head;
      int i = 1;
      while (curr != NULL) {
         cout << endl << i++ << "." << endl;
         curr->PrintPlaylistNode();
         curr = curr->GetNext();
      }
   }
}

#include <iostream>
#include <cmath>
#include <string.h>

using namespace std;

int main() {

    string tickerName;
    int numOfContracts;
    float currentOptionValue;

    cout << "Enter a stock ticker: ";
    getline(cin, tickerName);

    cout << "Enter the current number of " << tickerName << " contracts you are holding: ";
    cin >> numOfContracts;


    cout << "Enter the current price of the option: ";
    cin >> currentOptionValue;


    cout << "The value of your " << tickerName << " options are: $" << (currentOptionValue * 100.00) * (numOfContracts);

    cout << endl;

    return 0;
}

// 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 <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 <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.
	}

	}
	
}