概率算法思想

蒙特卡罗求圆周率

import java.util.Scanner;

public class Z {

    public static void main(String[] args) {
        long n;double pi;
        Scanner sc=new Scanner(System.in);

        System.out.println("输入点的数量n=");

        n=sc.nextInt();
        pi=method(n);
        System.out.println("pi="+pi);
    }

    private static double method(long n) {
        double pi,x,y;
        int count=0;
        for(long i=1;i<n;i++){
            x=Math.random();
            y=Math.random();//产生0到1之间的随机数x和y
            if((x*x+y*y)<=1){
                count++;
            }
        }
        pi=4.0*count/n;
        return pi;
    }

}