2023.4.13

//c++语言程序设计第二章习题
//2-24
#include <iostream>
using namespace std;
int main()
{
    Flag:
    cout<<"现在正在下雨吗？是（Y）否（N）"<<endl;
    char c;
    cin>>c;
    if(c == 'Y')
        cout<<"现在正在下雨"<<endl;
    else if(c == 'N')
        cout<<"现在没有下雨"<<endl;
    else
        goto Flag;
    return 0;
}

//c++语言程序设计第二章习题
//2-25
#include <iostream>
using namespace std;
int main()
{
    int score;
    cout<<"你考试考了多少分？（0~100）"<<endl;
    cin>>score;
    if(score>=90&&score<=100)
        cout<<"优"<<endl;
    if(score>=80&&score<90)
        cout<<"良"<<endl;
    if(score>=60&&score<80)
        cout<<"中"<<endl;
    if(score>=0&&score<60)
        cout<<"差"<<endl;
    return 0;
}

//c++语言程序设计第二章习题
//2-26
#include <iostream>
using namespace std;
int main()
{
 Flag:
    char c;
    cout<<"Menu:A(dd)D(elete)S(ort)Q(uit),select one:"<<endl;
    cin>>c;
        switch(c)
        {
            case 'A':cout<<"数据已经增加"<<endl;
                break;
            case 'D':cout<<"数据已经删除"<<endl;
                break;
            case 'S':cout<<"数据已经排序"<<endl;
                break;
            case 'Q':break;
        }
        if(c != 'Q')
        {
            goto Flag;
        }
    return 0;
}

//c++语言程序设计第二章习题
//2-27
#include <iostream>
using namespace std;
int main()
{
    for(int i = 2;i<=100;i++)
    {
        for(int j = 2;j<=i;j++)
        {
            if(i%j == 0&&i!=j)
                break;
            if(i == j)
                cout<<i<<"\t";
        }
    }
    return 0;
}