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Takes hours for program to run

Stoneynine (11)
When I run the program it takes a few hours to print the screen.

Can you help me figure out why it's taking so long to just print the screen? 

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#include <iostream>
#include <stdlib.h>
#include <random>
#include <time.h>
#include <windows.h>
#include <tuple>

using namespace std;

char obstacle[50][50];

int x = 0;
int y = 0;
int rx = 0;
int ry = 0;
int rcx = 0;
int rcy = 0;


tuple <int, int> Obstacle_generate()
{
        srand(time(0));
        int rx = rand()%50+0;
        int ry = rand()%50+0;

        return make_tuple (ry,rx);
}

tuple <int, int> Player_generate()
{
        srand(time(0));
        int rcx = rand()%50+0;
        int rcy = rand()%50+0;

        return make_tuple (rcy,rcx);
}

void Check_obstacle()
{
    bool ob_bool = false;
    tuple <int,int> t_obstacle;

            while(ob_bool != true)
        {
            t_obstacle = Obstacle_generate();

            ry = get<0>(t_obstacle);
            rx = get<1>(t_obstacle);

            if (obstacle[ry][rx] != 'O' && obstacle[ry][rx] != 'X')
            {
                obstacle[ry][rx] = 'O';
                ob_bool = true;
            }
        }
}

void Check_player()
{
    bool pl_bool = false;
    tuple <int,int> player;

        while(pl_bool != true)
        {
            player = Player_generate();

            rcy = get<0>(player);
            rcx = get<1>(player);

            if (obstacle[rcy][rcx] != 'O' && obstacle[rcy][rcx] != 'X')
            {
                obstacle[rcy][rcx] = 'X';
                pl_bool = true;
            }
        }

}

void Game_screen()
{

    int ob_count = 0;

    bool ob_check;
    bool pl_check;

    Check_player();

    for(y = 0; y < 50; y++)
    {
            for(x = 0; x < 50; x++)
            {
                ob_check = false;

                Check_obstacle();

                if(obstacle[y][x] != obstacle[ry][rx] && obstacle[y][x] != obstacle[rcy][rcx])
                {
                    obstacle[y][x] = ' ';
                    cout << obstacle[y][x] ;
                }

                else if(obstacle[y][x] == obstacle[ry][rx] && ob_check == false)
                {
                    cout << obstacle[ry][rx];
                    ob_check = true;
                }

                else if(obstacle[y][x] == obstacle[rcy][rcx] && pl_check == false)
                {
                    cout << obstacle[rcy][rcx];
                    pl_check = true;
                }
            }
        cout << "\n";
    }
    cout << "\n";
}

void Move_input()
{

}

void Clear_screen()
{

    system("cls");
}

void End_game()
{
    cout << "end game";
}

int main()
{

    string GAME;
    long long int count = 0;

    cout << "Type start to play.\n\n";

    cin >> GAME;
    if (GAME == "start")
    {
        do{
                cout << count;
            Clear_screen();
            Game_screen();
            cin >> GAME;
            Move_input();
        count++;
        }while(GAME != "quit");
    }

    End_game();
    return 0;
}
Last edited on
MiiNiPaa (8886)
You should not initialise random seed each time when you call function.
Remove all srand(time(0)) and place a single one as first line in main()
Due to the way your program designed, all functions using srand() can block your program for at least a second.
helios (17574)
Call srand() just once at the start of the program.

To understand why this makes a difference, suppose this is how rand() is implemented:
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int next_value;

void srand(int x){
    next_value = x;
}

int rand(){
    return next_value++;
}
Knowing that time(0) gets the current time in seconds, can you guess what will happen?
Stoneynine (11)
Thanks MiiNiPaa and helios for your advice, it worked.

@helios I don't think I understand what you're trying to ask me. If I understand correctly the output wouldn't be random and will actually output a pattern.

But I do know that this implementation of a random number generator isn't really that good at being random. So now the trouble is how do I implement a true random device into the code.

Fixed code:

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#include <iostream>
#include <stdlib.h>
#include <random>
#include <time.h>
#include <windows.h>
#include <tuple>
#include <functional>

using namespace std;

char obstacle[50][50];

int x = 0;
int y = 0;
int rx = 0;
int ry = 0;
int rcx = 0;
int rcy = 0;

tuple <int, int> Obstacle_generate()
{
        int rx = rand()%50+0;
        int ry = rand()%50+0;

        return make_tuple (ry,rx);
}

tuple <int, int> Player_generate()
{
        int rcx = rand()%50+0;
        int rcy = rand()%50+0;

        return make_tuple (rcy,rcx);
}

void Check_obstacle()
{
    bool ob_bool = false;
    tuple <int,int> t_obstacle;

            while(ob_bool != true)
        {
            t_obstacle = Obstacle_generate();

            ry = get<0>(t_obstacle);
            rx = get<1>(t_obstacle);

            if (obstacle[ry][rx] != 'O' && obstacle[ry][rx] != 'X')
            {
                obstacle[ry][rx] = 'O';
                ob_bool = true;
            }
        }
}

void Check_player()
{
    bool pl_bool = false;
    tuple <int,int> player;

        while(pl_bool != true)
        {
            player = Player_generate();

            rcy = get<0>(player);
            rcx = get<1>(player);

            if (obstacle[rcy][rcx] != 'O' && obstacle[rcy][rcx] != 'X')
            {
                obstacle[rcy][rcx] = 'X';
                pl_bool = true;
            }
        }

}

void Game_screen()
{

    int ob_count = 0;

    bool ob_check;
    bool pl_check;

    Check_player();

    for(y = 0; y < 50; y++)
    {
            for(x = 0; x < 50; x++)
            {
                ob_check = false;

                Check_obstacle();

                if(obstacle[y][x] != obstacle[ry][rx] && obstacle[y][x] != obstacle[rcy][rcx])
                {
                    obstacle[y][x] = ' ';
                    cout << obstacle[y][x] ;
                }

                else if(obstacle[y][x] == obstacle[ry][rx] && ob_check == false)
                {
                    cout << obstacle[ry][rx];
                    ob_check = true;
                }

                else if(obstacle[y][x] == obstacle[rcy][rcx] && pl_check == false)
                {
                    cout << obstacle[rcy][rcx];
                    pl_check = true;
                }
            }
        cout << "\n";
    }
    cout << "\n";
}

void Move_input()
{
       //empty
}

void Clear_screen()
{

    system("cls");
}

void End_game()
{
    cout << "end game";
}

int main()
{

    string GAME;
    long long int count = 0;

    srand(time(0)); //This was moved to here@@@@@@@

    cout << "Type start to play.\n\n";

    cin >> GAME;
    if (GAME == "start")
    {
        do{
                cout << count;
            Clear_screen();
            Game_screen();
            cin >> GAME;
            Move_input();
        count++;
        }while(GAME != "quit");
    }

    End_game();
    return 0;
}


MiiNiPaa (8886)
helios is telling you, that if you do, for example, srand(5), next rand() will return, say, 3. If you do srand(5) again, rand() will return 3 again.
time() returns time in secons on Windows machine. And program can make thousands of function calls in that second. Having srand() in each function that uses rand() means that all numbers generated in same second will bethe same.

There was your problem: check_obstacle() generates obstacle, rejects it, generates again same obstacle (because you had srand(time(0))), rejects it... etc.
Until second changes. Then you have another chance. If it will be rejected again, you need to wait for next second again...
Stoneynine (11)
Oh wow, I see now.
Thanks for explaining it to me.
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