1 #include<iostream> 2 #include<cctype> 3 using namespace std; 4 int main() 5 { 6     char arr[80]; 7     char ch; 8     cin.getline(arr,80); 9     int i=0;10     ch=arr[0];11     while((ch!=‘@‘)&&(i<=80))12     {13         if((ch>=‘a‘)&&(ch<=‘z‘))cout<<char(toupper(ch));14         else if((ch>=‘A‘)&&(ch<=‘Z‘))cout<<char(tolower(ch));15         else cout<<ch;16         i++;17         ch=arr[i];18     }19     return 0;20 }

 1 #include<iostream> 2 #include<cctype> 3 using namespace std; 4 int main() 5 { 6     double temp; 7     double donation[10]; 8     double sum=0; 9     int count=0;10     double ave=0;11     int i;12     for(i=0;i<10&&cin>>temp;i++)13     {14         donation[i]=temp;15         sum+=donation[i];16     }17     ave=sum/i;18     for(int j=0;j<i;j++)19     {20         if(donation[j]>ave)count++;21     }22     if(i!=10)cout<<"input error"<<endl;23     cout<<"the number of digit you have input "<<i<<endl;24     cout<<"ave="<<ave<<endl;25     cout<<"count="<<count<<endl;26     return 0;27 }