C++ 流程控制结构 (4)

#include <iostream>
using namespace std;

int main4() {

    /*
    * --------------------------------------------------------------------------------------------------------
    *选择结构
     */
     //if语句
     while (true) {
         int soure = 0;
         cout << "请用户输入分数：" << endl;
         cin >> soure;


         if (soure >= 600) {
             cout << "恭喜你，考入了清华";
         }
         else if (soure < 600 && soure >= 500) {
             cout << "恭喜你，考入了北大";
         }
         else {
             cout << "恭喜你，考入了杂牌大学";
         }
     }

     //三目运算符 表达式1?表达式2:表达式3
    int a = 1;
    int b = 2;
    string c = "";

    a > b ? c = "a大" : c = "b大";
    cout << c << endl;

    //switch 
    int a2 = 10;
    switch (a2) {
    case 1:
        cout << "a2 = 1 " << endl;
        break;
    case 2:
        cout << "a2 == 2" << endl;
        break;
    case 3:
        cout << "a2 ==3 " << endl;
        break;
    default:
        cout << "a2不等于1，2，3" << endl;
    }

    /*
    * --------------------------------------------------------------------------------------------------------
    *循环结构
     */
     //while循环
    int a3 = 0;
    while (a3 < 10) {
        cout << a3 << endl;
        a3++;
    }
    //while循环小游戏练习 猜数字
    int number = rand() % 100 + 1;
    cout << "猜数字,请输入数字 答案是:" << number << endl;
    int qu = 0;
    while(true) {
        cin >> qu;
        if (qu > number) {
            cout << "您输入的数字过大了" <<endl;
        }
        else if (qu < number) {
            cout << "您输入的数字过小了" <<endl;
        }
        else {
            cout << "恭喜您猜对了" << endl;
            break;
        }
    }
    cout << "游戏结束" << endl;

    //do while循环 
    // 语法 do{ 循环内容}while(条件判断); 与while不同的是 do while需要先执行内容，在进行条件判断

    //for 循环
    for (int i = 0; i < 10; i++) {
        cout << i << endl;
    }
    //for循环乘法口诀表
    for (int x = 1; x < 10; x++) {
        for (int y = 1; y <= x; y++) {
            cout << y << " x " << x << " = " << x * y << "\t";
        }
        cout << "\n";
    }

    /*
    * --------------------------------------------------------------------------------------------------------
    *跳转语句
     */
     //break 用于跳出选择结构或者循环结构
     //continue  在循环语句中，跳过本次循环中尚未执行完成的语句，继续执行下一次循环
     //goto 无条件跳转语句

    cout << "1" << endl;
    goto  AAA;
    cout << "2" << endl;
    cout << "3" << endl;
    AAA:
    cout << "4" << endl;
    cout << "5" << endl;

}