##### Write a program to solve N-Queens problem using Prolog.
```				```
#define N 4#include <stdbool.h>

#include <stdio.h>

void printSolution(int board[N][N]) {
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++)
printf(" %d ", board[i][j]);
printf("\n");
}
}
bool isSafe(int board[N][N], int row, int col) {
int i, j;
/* Check this row on left side */
for (i = 0; i < col; i++)
if (board[row][i])
return false;
/* Check upper diagonal on left side */
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;
}
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))
return true;
board[i][col] = 0; // BACKTRACK
}
}
return false;
}
bool solveNQ() {
int board[N][N] = {
{ 0, 0, 0, 0 },
{ 0, 0, 0, 0 },
{ 0, 0, 0, 0 }
};
if (solveNQUtil(board, 0) == false) {
printf("Solution does not exist");
return false;
}
printSolution(board);
return true;
}
int main() {
solveNQ();
return 0;
}
```
```