c++学习课时二 简单的判断&&循环

建议一下代码根据注释一段一段敲，改变数值去理解每一个语法的奥妙...............

# include<stdio.h>#include "stdafx.h"#include "iostream"using namespace std;void function();int main(){function();return 0;}void function(){//判断的/*-------if语句(判断a的值)-------*/int a;        //定义一个变量aa = 1;        //给a赋值=1if (a = 1){cout << "a的值是1\n";}else{}if (a != 1){cout << "a的值不是1\n";}else{cout << "a的值是" << a<<"\n";}/*-------switch语句（判断成绩为abcde的分数）-------*/char grade = 'b';switch (grade){case 'a': cout << "90--100\n"; break;case 'b': cout << "80--99\n"; break;case 'c': cout << "70--79\n"; break;case 'd': cout << "60--69\n"; break;case 'e': cout << "<60\n"; break;default:cout << "error\n";}/*-------if和else if的搭配相当于switch（判断成绩为abcde的分数）-------*/if (grade == 'a'){cout << "90--100\n";}else if (grade == 'b'){cout << "80--99\n";}else if (grade == 'c'){cout << "70--79\n";}else if (grade == 'd'){cout << "60--69\n";}else if (grade == 'e'){cout << "<60\n";}else{cout << "error\n";}//循环语句/*-------for循环（从1循环到10输出3遍）-------*/for (int i = 1; i <= 3; i++){//cout << i<<"\n";for (int j = 1; j <= 10; j++){cout << j << "\n";}}/*-------while循环（从100循环到110）-------*/int num = 100;while (num<=110){cout << num << "\n";++num;}/*-------do-while循环(当num_1结果等于103的时候输出我是103)-------*/int num_1 = 100;do{num_1++;}while (num_1 == 103);cout << "我是103\n";system("pause");}