面试题之随机答题(c++)

对随机生成的运算式进行计算，如果回答正确，加分，若错误，会扣分。答题失败后会给第二次机会答题，再失败则扣除对应分数并提示正确答案。并有答题时间统计。

下面是程序和说明（环境：VS2013）

project.h

#ifndef __PROJECT_H__
#define __PROJECT_H__

#include <iostream>
#include <ctime>
#include <cstdlib>

using namespace std;

class pro
{
public:
	int score = 0;
	int cnt = 0;
	void srandR(int a,int b);
	void showResult();

private:
	int m_a;
	int m_b;
	int m_c;
	int m_value;
	int m_Result;
};


#endif

  project.cpp

#include "project.h"

void pro::showResult()
{
	while (1)
	{
		cin >> m_value;

		if (m_Result == m_value)
		{
			cout << "回答正确!" << endl;
			score += 20;
			break;
		}
		else
		{
			if (cnt == 0)
			{
				cout << "回答错误，请重新回答：";
				score -= 10;

			}
			cnt++;
			if (cnt == 2)
			{
				cout << "回答错误，答案是：" << m_Result << endl;
				cnt = 0;
				score -= 20;
				break;
			}
			continue;

		}

	}//end for while
}

void pro::srandR(int a,int b)
{
	m_a = a;
	m_b = b;

	srand((unsigned)time(NULL));

	//产生1-4的随机数
	m_c=rand() % 4 +1;
	cout << m_c;
	switch (m_c)
	{
	case 1:
		m_Result = m_a + m_b;
		cout << m_a << "+" << m_b <<"=";
		break;
	case 2:
		m_Result = m_a - m_b;
		cout << m_a << "-" << m_b << "=";
		break;

	case 3:
		m_Result = m_a * m_b;
		cout << m_a << "*" << m_b << "=";
		break;

	case 4:
		m_Result = m_a / m_b;
		cout << m_a << "/" << m_b << "=";
		break;

	default:
		break;
	}
	showResult();
}

main.cpp

#include "project.h"

int main()
{
	int begin_time, end_time , spendTime= 0;
	pro p;

	srand((unsigned)time(NULL));

	begin_time = clock();
	for (int i = 0; i < 5; i++)
	{
		cout << "第" << i + 1 << "题:";
		//产生1-10的随机数
		int a = rand() % 10 + 1;
		int b = rand() % 10 + 1;
		p.srandR(a, b);
	}
	end_time = clock();

	spendTime = (end_time - begin_time) / CLOCKS_PER_SEC;

	cout << "答题结束，你所获得的分数是：" << p.score << endl;
	cout << "你所花费的时间是：" << spendTime <<"秒"<< endl;

	return 0;
}

该项目还可以改善一下：如把分数和时间放入结构体中，再把每次获得结果的结构体对象存入结构体list中，重载 < 或者 > 运算符，可以实现多个玩家的分数比较，分数相同则比较时间长短。因此处涉及STL的容器算法，固不放在c++基础知识中讨论。