一、输入一个数字，为其高，一个符号*，输出该符号组成的平行四边形形状。

#include <iostream>
using namespace std;

int main() {

	int num;
	cin >> num;			//输入数字

	for (int i = 1; i < num+1; i++) {		//打印num行
		for (int j = 1; j < i; j++) {		//打印空格
			cout << " ";
		}
		for (int j = 1; j < num + 1; j++) {		//打印*
			cout << "*";
		}
		cout << endl;		//换行
	}
}

二、是猴子吃桃问题，每天都吃剩下的一半，再多吃一个，直到第十天剩下一个桃子，问第一天猴子有多少个桃。

#include <iostream>
using namespace std;


int cal(int n) {
	if (n == 10) {		
		return 1;	//第十天只剩一个桃子
	}
	else {
		return (cal(n + 1) + 1 )* 2;		//根据题目意思列出等式
	}

}

int main() {
	int answer = cal(1);		//调用递归算法，传入参数1（第一天开始计算）
	cout << "总共有：" << answer << "个桃子";
	return 0;
}

三、输入一系列的数字，输出他们正负数个数，输入0截止，要用函数实现 。

#include <iostream>
using namespace std;

int count1 = 0, count2 = 0;

void judge(int temp) {
	if (temp > 0) {
		count1++;
	}
	else {
		count2++;
	}
}

int main() {
	double temp;
	cin >> temp;
	while (abs(temp)>1e-6) {		//判断是否等于0
		judge(temp);				//调用函数
		cin >> temp;
	}
	cout << "正数：" << count1 << "个" << endl;		//输出
	cout << "负数：" << count2 << "个" << endl;
	return 0;

}

四、用一个类来记录学生成绩和他班级，里面有几个函数，静态成员和动态成员都有。

#include <iostream>
#include<string>
using namespace std;

class Student {
private:
	string name;		//学生姓名
	double score;		//学生分数
	string className;	//学生班级名
	static double sum;	//全部总分
	static int stuNum;	//学生总数
public:
	Student(string n, double s, string c);	//有参构造函数	
	static double getSum();		//求总分
	static double getAverage();		//求平均分
	void stuDisplay();			//输出每个学生信息
	static void totalInforDisplay();	//展示总信息
};

double Student::sum = 0;		//初始化静态变量
int Student::stuNum = 0;

Student::Student(string n, double s, string c) {
	name = n;
	score = s;
	className = c;
	stuNum++;
	sum += score;
}

double Student::getSum() {
	return sum;
}

double Student::getAverage() {
	return sum / stuNum;
}

void Student::stuDisplay() {
	cout << "name:" << name << endl;
	cout << "score:" << score << endl;
	cout << "className:" << className << endl;
}

void Student::totalInforDisplay() {
	cout << "sum:" << getSum() << endl;
	cout << "average:" << getAverage()<<endl;
}


int main() {
	Student stu[5] = {
		Student("Obama",99.0,"1"),
		Student("Mike",77.5,"1"),
		Student("Jackson",87.0,"2"),
		Student("Cherry",93.5,"3"),
		Student("Oscar",89.0,"4")
	};
	for (int i = 0; i < 5; i++) {
		stu[i].stuDisplay();
		cout << endl;
	}
	Student::totalInforDisplay();

}

五、重载+，++，=等简单运算符

#include <iostream>
using namespace std;

class Time {
private:
	int hour;
	int minute;
	int second;
public:
	Time();		//无参构造函数
	Time(int h, int m, int s);	//有参构造函数
	Time operator + (Time& temp);	//重载+运算符
	Time operator++();			//重载前置++
	Time operator++(int n);		//重载后置++
	void operator=(Time& temp);	//重载赋值运算符
	friend ostream& operator <<(ostream& output, Time& temp);	//重载输出流
};

Time::Time() {
	hour = 0;
	minute = 0;
	second = 0;
}

Time::Time(int h, int m, int s) :hour(h), minute(m), second(s) {}

Time Time::operator+(Time& temp) {
	this->hour += temp.hour;
	this->minute += temp.minute;
	this->second += temp.second;
	return *this;
}

Time Time::operator++() {
	second++;
	if (second >= 60) {
		second = 0;
		minute++;
	}
	if (minute >= 60) {
		minute = 0;
		hour++;
	}
	if (hour >= 12) {
		hour = 0;
	}
	return *this;
}

Time Time::operator++(int n) {
	Time returnTime(*this);
	second++;
	if (second >= 60) {
		second = 0;
		minute++;
	}
	if (minute >= 60) {
		minute = 0;
		hour++;
	}
	if (hour >= 24) {
		hour = 0;
	}
	return returnTime;
}
void Time::operator=(Time& temp) {
	this->hour = temp.hour;
	this->minute = temp.minute;
	this->second = temp.second;
}
ostream& operator<<(ostream& output, Time& temp) {
	output << temp.hour << ":" << temp.minute << ":" << temp.second<<endl;
	return output;
}

int main() {
	Time t1(12, 12, 12);
	Time t = t1;
	for (int i = 0; i < 60; i++) {
		Time temp=t++;
		cout << temp;
	}
	cout << "************" << endl;
	t = t1;
	for (int i = 0; i < 60; i++) {
		Time temp = ++t;
		cout << temp;
	}
}