Como calcular o PI em C pelo Método de Monte Carlo

# include <stdio.h>

# include <stdlib.h>

# include <unistd.h>

# include <time.h>

# include <math.h>

int main(int argc, char *argv[])

{

                int N = 1000000;

                int n = 0;

                float x, y;

               

                srand( time( NULL ) );

                for(int i = 0; i < N; i++)

                {

                                x = (float) rand() / RAND_MAX;              

                                y = (float) rand() / RAND_MAX;

                               if(sqrt (x*x+y*y) <= 1)

                               {

                                               n++;

                               }

                }

                              

                float reasultado = (((float)4 * (float)n) / (float)N);

                printf("PI é igual a: %f", resultado);

                return 0;

}