potatoes

#include <stdio.h>
#include <stdlib.h>

#define N 8

void showGrid(int **grid);
int backtracking(int **grid, int l, int c);
int acceptable(int **grid, int ligne, int colonne);

int main(){
    int **grid;
    int i, j;

    grid = calloc(N, sizeof(int*));
    for(i=0; i<N; i++)
        grid[i] = calloc(N, sizeof(int));

    for(i=0; i<N; i++)
        for(j=0; j<N; j++)
            grid[i][j]= 0;

    backtracking(grid, 0, 0);
    return 0;

}

void showGrid(int **grid){
    int i, j;
    for(i=0; i<N; i++){
        for(j=0; j<N; j++)
            if(grid[i][j] != 0)
                printf("[%d] ", grid[i][j]);
            else
                printf("[ ] ");
        printf("\n");
    }
}

int acceptable(int ** grid, int ligne, int colonne){
    int i, j;
    //verification ligne - colonne
    for(i=0; i<N; i++){
        if(grid[i][colonne] == 1
            return 0;
        if(grid[ligne][i] == 1)
            return 0;
    }

    //verification diagonales
    j = colonne;
    for(i = ligne; i<N && j<N; i++){
        if( grid[i][j] == 1)
            return 0;
        j++;
    }

    j = colonne;
    for(i = ligne; i>= 0 && j >=0; i--){
        if(grid[i][j] == 1)
            return 0;
        j--;
    }

    j = colonne;
    for(i= ligne; i<N && j>= 0; i++){
        if(grid[i][j] == 1)
            return 0;
        j--;
    }

    j = colonne;
    for(i=ligne; i>=0 && j<N; i--){
        if(grid[i][j] == 1)
            return 0;
        j++;
    }

    return 1;
}

int backtracking(int **g, int l, int c){
    int colonne;

    for(colonne = c; colonne <N; colonne ++){
        if(acceptable(g, l, colonne) == 1){
            g[l][colonne] = 1;
            printf("\n");
            showGrid(g);
            backtracking(g, l+1, 0);
        }else
            g[l][colonne] = 0;
    }
}