hitormiss.c

hitorMiss＋用概率算法求积分问题的C程序

#include"stdio.h"
#include"stdlib.h"
#include"time.h"
#include"math.h"

double uniform();
double hitorMiss(int);

void main(){
	int n = 10000000;
	double pie = hitorMiss(n);
	printf("%f",pie);
}

double hitorMiss(int n){
	int k = 0;
	srand( (unsigned)time( NULL ) );	
	for(int i = 1; i <= n; i++){
		double x = uniform();
		double y = uniform();
		if(y <= sqrt(1.0 - x*x))
			k++;
	}
	return 4.0 * (double)k / (double)n;
}

double uniform(){
	int j = rand();
	double k = ((double)j) / ((double)RAND_MAX);
	return k;
}