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Anyone knows whats up?

masecla33 (71)
Its a game of life. Loads everything from inp.in.
Tough after the first step everything dies. Any ideas? Please explain if you have something, don't just do my work.
Here is what inp.in contains:
1 1 0 1 1
1 1 0 1 0
0 0 1 0 0
0 0 0 0 0

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  #include <iostream>
#include <fstream>

using namespace std;
struct space
{
    bool state;
};
struct grid
{
    int sizes;
    space cell[100][100];
    void sSwitch(int x,int y)
    {
        cell[x][y].state=(cell[x][y].state==0);
    }
    int getmany(int x,int y)
    {
        int howmany=0;
        if(cell[(x-1)][y].state==1)
            howmany++;
        if(cell[(x-1)][(y-1)].state==1)
            howmany++;
        if(cell[(x-1)][(y+1)].state==1)
            howmany++;
        if(cell[(x)][(y-1)].state==1)
            howmany++;
        if(cell[(x)][(y+1)].state==1)
            howmany++;
        if(cell[(x+1)][y].state==1)
            howmany++;
        if(cell[(x+1)][(y+1)].state==1)
            howmany++;
        if(cell[(x+1)][(y+1)].state==1)
            howmany++;
    }
    int getcell(int x,int y)
    {
        return cell[x][y].state;
    }
    void showGrid()
    {
        for(int i=0; i<sizes; i++)
        {
            for(int j=0; j<sizes; j++)
                cout<<getcell(i,j)<<" ";
            cout<<endl;
        }
    }
    void showGridMany()
    {
        int a[100][100];
        for(int i=0; i<sizes; i++)
        {

            for(int j=0; j<sizes; j++)
            {
                a[i][j]=getmany(i,j);
                cout<<a[i][j]<<" ";
            }
        cout<<endl;
        }
    }
    void nextStep()
    {
        int a[100][100];
        for(int i=0; i<sizes; i++)
            for(int j=0; j<sizes; j++)
                a[i][j]=getmany(i,j);
        for(int i=0; i<sizes; i++)
        {
            for(int j=0; j<sizes; j++)
            {
                if(cell[i][j].state==1)
                {
                    if(a[i][j]<2)
                    {
                        sSwitch(i,j);
                        cout<<"Switched "<<i<<" "<<j<<endl;
                    }
                    if(a[i][j]>3)
                    {
                        sSwitch(i,j);
                    cout<<"Switched "<<i<<" "<<j<<endl;

                    }
                }
                else
                {
                    if(a[i][j]==3)
                    {
                        sSwitch(i,j);
                    cout<<"Switched "<<i<<" "<<j<<endl;
                    }
                }
            }
        }
    }
    void loadFrom(char name[255])
    {
        ifstream fin(name);
        for(int i=0; i<sizes; i++)
            for(int j=0; j<sizes; j++)
                fin>>cell[i][j].state;
    }
};
int main()
{
    grid mygrid;
    mygrid.sizes=5;
    mygrid.loadFrom("inp.in");
    mygrid.showGrid();
    cout<<"\n\n";
    cout<<mygrid.getmany(1,1)<<endl;
    mygrid.showGridMany();
    cout<<endl;
    mygrid.nextStep();
    mygrid.showGrid();
    return 0;
}
Peter87 (11226)
You forgot to return howmany from getmany.
masecla33 (71)
Thanks man. Such a silly mistake I've made there. Thanks ;)
Peter87 (11226)
It was quite easy for me to spot because the compiler told me.

My compiler wrote:
test.cpp:36:5: warning: no return statement in function returning non-void [-Wreturn-type]

Most compilers are able to warn you about simple mistakes like this. If you're using GCC/MinGW/Clang I strongly recommend compiling the code with at least the -Wall compiler flag.

https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
masecla33 (71)
I did get that warning as well, tough i ignored it xD
Chervil (7320)
Though it is only a warning, it should be considered an error in most circumstances.
Here for example, if the call to function two() is uncommented, it will probably cause a program error.
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#include <iostream>
#include <string>

using namespace std;

int one() { }

string two() { }

int main()
{
    cout << one() << '\n';
    // cout << two() << '\n'; this line probably cause a crash

    cout << "Done\n";
}


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