C++实验一

2-28

#include <iostream>
using namespace std;
int main()
{char x;
 cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
  cin>>x;
 while(x)
 {if (x=='A')
      {cout<<"Date add"<<endl;
      }
   else
       if (x=='D')
          {cout<<"Date delete"<<endl;
          }
   else
       if (x=='S')
          {cout<<"Date sort"<<endl;
          }
           else if(x=='Q')
               break;
               else cout<<"Date error"<<endl;
  cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
  cin>>x;
 }
return ;
}

（1）

#include <iostream>
using namespace std;
int main()
{char x;
 cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
  cin>>x;
 while(x)
 {switch(x)
     {case  'A':
           cout<<"Date add"<<endl;
           break;
      case  'D':
           cout<<"Date delete"<<endl;
           break;
      case  'S':
           cout<<"Date sort"<<endl;
           break;
      default:
           cout<<"Date quit"<<endl;       

 }
 if(x=='Q')
   break;
 cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
 cin>>x;
 }
return ;
}

（2）

2-29

#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
    int t = , i, j = , flag;
    while (j < )
    {
        flag = ;
        i = ;
        while (i <= j - )
        {
            if (j%i++ == )
            {
                flag = ;
                break;
            }
        }
        if (flag == )
        {
            t++;
            cout << setw()<<j ;
            if (t %  == )
                cout << endl;
        }
        j++;
    }
    return ;
}

（1）

#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
    int t = , i, j = , flag;
    do
    {
        flag = ;
        i = ;
        while (i <= j - )
        {
            if (j%i++== )
            {
                flag = ;
                break;
            }
        }
        if (flag == )
        {
            t++;
            cout << setw() << j;
            if (t %  == )
                cout << endl;
        }
        j++;
    }while (j < );
    return ;
}

（2）

#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
    int t = , i, j = , flag;
    for (;j < ;j++)
    {
        flag = ;
        i = ;
        for (;i <= j - ;i++)
        {
            if (j%i== )
            {
                flag = ;
                break;
            }
        }
        if (flag == )
        {
            t++;
            cout << setw() << j;
            if (t %  == )
                cout << endl;
        }
    }
    return ;
}

（3）

2-32

#include <iostream>
using namespace std;
int main()
{int i=, j;
 cin >> j;
 while (i != j)
 {
     if (j > i)
         cout << "bigger than the number" << endl;
     if (j < i)
         cout << "lower than the number" << endl;
     cin >> j;
 }
 cout <<"Congratulations!You guess it."<< endl;
    return ;
}

（1）

#include <iostream>
using namespace std;
int main()
{
    int i = , j;
    cin >> j;
    do
    {
        if (j > i)
            cout << "bigger than the number" << endl;
        if (j < i)
            cout << "lower than the number" << endl;
        cin >> j;
    }while (i != j);
    cout << "Congratulations!You guess it." << endl;
    return ;
}

（2）

2-34

#include<iostream>
using namespace std;
int main()
{int a, b, c;
 cout << "red:0,yellow:1,blue:2,white:3,black:4"<<endl;
 for (a = ;a < ;a++)
 {
     for (b = a + ;b < ; b++)
     {
         if (a == b) continue;
         for (c = b + ;c < ;c++)
         {
             if (c == a || c == b) continue;
             cout << a << b << c << endl;
         }
     }
 }
return ;
}

（0）

总结：要好好学习，加油鸭~

https://www.cnblogs.com/syf1/p/10561928.html

https://www.cnblogs.com/fearless04/p/10543040.html

https://www.cnblogs.com/Yyaoyyy/p/10547742.html