poj-3440-Coin Toss

直接推出来公式算面积。

然后求百分比。

#include<stdio.h>
#include<string.h>
#include<iostream>
#include<algorithm>
#include<math.h>
using namespace std;
#define PI (acos(-1.0))
int main()
{
    int T;
    double m,n,t,c;
    double a1,a2,a3,a4,a;
    scanf("%d",&T);
    for(int _=1;_<=T;_++)
    {
         scanf("%lf%lf%lf%lf",&m,&n,&t,&c);
         c=c/2;
         a1=a2=a3=a4=0.0;
         a3=a4=(n-1)*(m-1);
         a4=a4*c*c*PI;
         a3=a3*(4*c*c-PI*c*c);
         a2=n*(m-1)+m*(n-1);
         a2=a2*(t-2*c)*2*c;
         a2=a2+c*c*2*(m+n-2)*2;
         a=m*n*t*t;
         a1=a-a2-a3-a4;
         printf("Case %d:\n",_);
         printf("Probability of covering 1 tile  = %.4f%%\n",(100.0*a1/a));
         printf("Probability of covering 2 tiles = %.4f%%\n",(100.0*a2/a));
         printf("Probability of covering 3 tiles = %.4f%%\n",(100.0*a3/a));
         printf("Probability of covering 4 tiles = %.4f%%\n",(100.0*a4/a));
         if(_!=T)cout<<endl;
    }
    return 0;
}

poj-3440-Coin Toss

原文：http://blog.csdn.net/rowanhaoa/article/details/18261077