C11-我的储蓄计划

一、课堂案例

while(){

}
当（条件满足）{
    执行循环体
}

#include<iostream>
using namespace std;
int main()
{
    string name;	//字符串  stl
    double price, income, pay, sum = 0;
    cout << "请输入需要购买的商品名称:";
    cin >> name;
    cout << "请输入商品的价格：";
    cin >> price;
    cout << "您需要购买的商品名称是：" << name << "，价格为：" << price<<"元。\n";

    int week=1;
    while (sum < price) {
        cout << "请输入第"<<week<<"周的收入：";
        cin >> income;
        cout << "请输入第"<<week<<"周的支出：";
        cin >> pay;
        sum += income - pay;
        cout << "当前的小金库共有：" << sum << "元。\n";
        price = price * 1.1;
		cout << "本周的商品价格为：" << price << endl; 
        ++week;	//week += 1;
//        if (sum >= price){
//        	cout << "可以去购买啦！";
//			break;
//		}
    }
    cout << "可以去购买啦！";

    return 0;
}

二、实例

1. 实例1： 循环输出1~n之间的偶数

#include<iostream>
using namespace std;
int main()
{
    int n;
    cin >> n;
    int i=1;
    while (i <= n) { //当条件满足执行 
    	if (i%2==0){
    		cout << i << ' ';
		} 
        i++;
    }
    return 0;
}