c++作业2

2-28

include

using namespace std;
int main()
{
char i;
cout<<"Menu:A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
do{

cin>>i;
switch(i)
{
	case 'A':
	cout<<"data has been added."<<endl;
	break; 
	case'D':
	cout<<"data has been deleted."<<endl;
	break; 
	case'S':
	cout<<"data has been sort"<<endl;
	break; 
}

}while(i!='Q');
return 0;
}

2-29
//while语句//

include

include

using namespace std;
int judge(int);
int main()
{
int i=2,j;
while(i<=100)
{
if(judge(i))
cout<<i<<endl;
i++;
}
return 0;
}
int judge(int j)
{
int i,flag=1;
for(i=2;i<=sqrt(j);i++)
{
if(j%i==0)
{
flag=0;
break;
}
}
return flag;
}
// do while//

{
	if(judge(i))
	cout<<i<<endl;
	i++;
}while(i<=100);

return 0;
}
int judge(int j)
{
int i,flag=1;
for(i=2;i<=sqrt(j);i++)
{
if(j%i==0)
{
flag=0;
break;
}
}
return flag;
}
//for//

include

include

using namespace std;
int judge(int);
int main()
{
int i=2,j;
for(i=2;i<=100;i++)
{
if(judge(i))
cout<<i<<endl;

}

return 0;
}
int judge(int j)
{
int i,flag=1;
for(i=2;i<=sqrt(j);i++)
{
if(j%i==0)
{
flag=0;
break;
}
}
return flag;
}
2-32
//while//

include

using namespace std;
int main()
{
int i,guess;
cin>>i;
while(i!=guess)
{
cout<<"Enter the number you guess:"<<"\n";
cin>>guess;
if(guess>i)
cout<<"The number is larger than the right one.Try again"<<"\n";
if(guess<i)
cout<<"The number is smaller than the right one.Try again"<<"\n";

}
cout<<"Congratulations!"<<endl; 

return 0;

}
//do while//

include

using namespace std;
int main()
{
int i,guess;
cin>>i;
do{
cout<<"Enter the number you guess:"<<"\n";
cin>>guess;
if(guess>i)
cout<<"The number is larger than the right one.Try again"<<"\n";
if(guess<i)
cout<<"The number is smaller than the right one.Try again"<<"\n";

}while(i!=guess);
cout<<"Congratulations!"<<endl; 

return 0;

}
2-34

include

include

using namespace std;
int main()
{
enum color{red,yellow,blue,white,black};
color pri;
int i,j,k,n=0,loop;
for(i=red;i<=black;i++)
{
for(j=red;j<=black;j++)
{
if(i!=j)
{
for(k=red;k<=black;k++)
{
if(k!=i&&k!=j)
{
n=n+1;
cout<<setw(3)<<n;
for(loop=1;loop<=3;loop++)
{
switch(loop)
{
case 1:pri=color(i);break;
case 2:pri=color(j);break;
case 3:pri=color(k);break;
default :break;
}

                        switch(pri)
                        {  
                        case red:cout<<setw(8)<<"red";break;  
                        case yellow:cout<<setw(8)<<"yellow";break;  
                        case blue:cout<<setw(8)<<"blue";break;  
                        case white:cout<<setw(8)<<"white";break;  
                        case black:cout<<setw(8)<<"black";break;  
                        default :break;  
                        }  
                    }  

                    cout<<endl;  
                }  
            }  
        }  
    }  
}  

cout<<"total:"<<n<<endl;
return 0;  

}