杭电1048The Hardest Problem Ever

#include<iostream>
#include<string>
using namespace std;
int main()
{
string s;
while (cin>>s)
{
if(s=="ENDOFINPUT")
break;
cin.ignore();
string str,r;
getline(cin,str);
cin>>r;
for(int i=0;i<str.size();++i)
{
if(str.at(i)<='E'&&str.at(i)>='A')
str.at(i)+=21;
else if(str.at(i)<='Z'&&str.at(i)>='F')
str.at(i)-=5;
else
continue;
}
cout<<str<<endl;
}
return 0;

}

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