Coin Toss--POJ 3440

1、解题思路：概率论，计算几何。

2、注意事项：题意理解圆心在m*n的矩形中运动；中间值用double类型记录；注意题干中的输出格式。

3、实现方法：

#include < iostream >
#include < math.h >
using namespace std;
#define PI 3.141592653

int main()
{
int num,i;
double m,n,t,c;
double pro1,pro2,pro3,pro4;
cin >> num;
for (i = 1 ;i <= num;i ++ )
{
cin >> m >> n >> t >> c;
double sq = m * n * t * t;
pro2 = (m - 1 ) * n * t * c + (n - 1 ) * m * t * c - 2 * (m - 1 ) * (n - 1 ) * c * c;
pro2 = pro2 / sq;

pro3 = (m - 1 ) * (n - 1 ) * c * c * ( 1 - PI / 4 );
pro3 = pro3 / sq;

pro4 = (m - 1 ) * (n - 1 ) * c * c * PI / 4 ;
pro4 = pro4 / sq;

pro1 = 1 - (pro2 + pro3 + pro4);

cout << " Case " << i << " : " << endl;
cout.setf(ios:: fixed );
cout.precision( 4 );
cout << " Probability of covering 1 tile = " << pro1 * 100 << " % " << endl;
cout << " Probability of covering 2 tiles = " << pro2 * 100 << " % " << endl;
cout << " Probability of covering 3 tiles = " << pro3 * 100 << " % " << endl;
cout << " Probability of covering 4 tiles = " << pro4 * 100 << " % " << endl;

if (i != num)
cout << endl;
}
return 0 ;
}

 

转载于:https://www.cnblogs.com/yongze103/archive/2010/07/26/1785428.html