void imprimeGrelha(char grid[N][N])
{
    //cria a grelha e imprime o tabuleiro
    printf(" %c | %c | %c \n--- --- ---\n %c | %c | %c \n--- --- ---\n %c | %c | %c \n", grid[0][0], grid[0][1], grid[0][2], grid[1][0], grid[1][1], grid[1][2],  grid[2][0], grid[2][1], grid[2][2]);

}