Data-Structures/N Queen Problem.cpp at master · Amisha-here/Data-Structures · GitHub

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#include<iostream>
using namespace std;
#define N 6

void Print(int matrix[N][N])
{
    for (int i = 0; i <N; i++)
    {
        for (int j = 0; j <N; j++)
        {
           cout<<" "<<matrix[i][j]<<" ";
        }
        cout<<endl;
    }
}
bool queen(int matrix[N][N], int r, int c)
{
    int i, j;
    for (i = 0; i < c; i++)
    {
        if (matrix[r][i])
        {
            return false;
        }
    }
    for (i = r, j = c; i >= 0 && j >= 0; i--, j--)
    {
        if (matrix[i][j])
        {
            return false;
        }
    }
    for (i = r, j = c; j >= 0 && i <N; i++, j--)
    {
        if (matrix[i][j])
        {
            return false;
        }
    }
    return true;
}
bool solve(int matrix[N][N], int c)
{
    if (c>=N)
    {
        return true;
    }
    for (int i = 0; i <N; i++)
    {
        if (queen(matrix, i, c))
        {
            matrix[i][c] = 1;
            if (solve(matrix, c + 1))
            {
                return true;
            }
            matrix[i][c] = 0;
        }
    }
    return false;
}
int main()
{
    int matrix[N][N] = { { 0, 0, 0, 0, 0 },
                         { 0, 0, 0, 0, 0 },
                         { 0, 0, 0, 0, 0 },
                         { 0, 0, 0, 0, 0 },
                         { 0, 0, 0, 0, 0 },
                         { 0, 0, 0, 0, 0 } };

    if (solve(matrix, 0) == false)
    {
        cout<<"Solution does not exist";
        return 0;
    }
    Print(matrix);
    return 0;
}