C++Primer Plus第七章函数---C++编程 7.3练4 关于彩票获奖的概念的问题

这道题，要完成之前，我买先来看下程序清单7.4的问题：获奖的概率


问题跑出来了。下面我们看这个问题的解决办法。

#pragma region calling.cpp 7.4
/*

*/
#if 1
#include <iostream>
// Note: some implementations require double instead of long double
long double probability(unsigned numbers, unsigned picks);
int main()
{
   
	using namespace std;
	double total, choices;
	cout << "Enter the total number of choices on the game card and\n"
		"the number of picks allowed:\n";
	while ((cin >> total >> choices) && choices <= total)
	{
   
		cout