题解

#include<bits/stdc++.h>
using namespace std;
string a;
int main()
{
    getline(cin,a);
    for(int i = 0; i < a.length(); i++)
    {
        if(a[i] >= 'a' && a[i] <= 'z')
        {
            char x = (a[i] - 'a' + 1) % 26 + 'a';
            char y = (a[i] - 'a' + 2) % 26 + 'a';
            char z = (a[i] - 'a' + 3) % 26 + 'a';
            cout << x << y << z;
        }
        else if(a[i] >= 'A' && a[i] <= 'Z')
        {
            char x = (a[i] - 'A' + 1) % 26 + 'A';
            char y = (a[i] - 'A' + 2) % 26 + 'A';
            char z = (a[i] - 'A' + 3) % 26 + 'A';
            cout << x << y << z;
        }
        else cout << a[i];
    }
    return 0;
}