# C++ Programming Code Examples

## C++ > Computer Graphics Code Examples

### C++ Program to Solve N-Queen Problem

``` C++ Program to Solve N-Queen Problem This C++ Program demonstrates the implementation of N-Queen Problem. #include <iostream> #include <cstdio> #include <cstdlib> #define N 8 using namespace std; /* print solution */ void printSolution(int board[N][N]) { for (int i = 0; i < N; i++) { for (int j = 0; j < N; j++) cout<<board[i][j]<<" "; cout<<endl; } } /* check if a queen can be placed on board[row][col]*/ bool isSafe(int board[N][N], int row, int col) { int i, j; for (i = 0; i < col; i++) { if (board[row][i]) return false; } for (i = row, j = col; i >= 0 && j >= 0; i--, j--) { if (board[i][j]) return false; } for (i = row, j = col; j >= 0 && i < N; i++, j--) { if (board[i][j]) return false; } return true; } /*solve N Queen problem */ bool solveNQUtil(int board[N][N], int col) { if (col >= N) return true; for (int i = 0; i < N; i++) { if ( isSafe(board, i, col) ) { board[i][col] = 1; if (solveNQUtil(board, col + 1) == true) return true; board[i][col] = 0; } } return false; } /* solves the N Queen problem using Backtracking.*/ bool solveNQ() { int board[N][N] = {0}; if (solveNQUtil(board, 0) == false) { cout<<"Solution does not exist"<<endl; return false; } printSolution(board); return true; } // Main int main() { solveNQ(); return 0; } ```