#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int main(void) {
e(null));
double a = 1;
double b = 2;
int count = 0;
double x,y;
for(int i=0; i<100000; i++){
x = (a)*rand() / (RAND_MAX + 1.);
y = (b)*rand() / (RAND_MAX + 1.);
if(x*x/a/a + y*y/b/b <= 1){
count++;
}
}
double s = 4*a*b*count/100000.;
return 0;
}