#include <iostream>
#include <string>
#include <algorithm>
#include <cctype>

using namespace std;

char change(char c){
    if(isupper(c)) return c +0x20;
    return c-0x20;
}

int main(){
    string s;
    cin >> s;
    transform(s.begin(), s.end(), s.begin(), change);
    cout << s << endl;
}