#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

int main(){
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	
	string s;
	cin >> s;
	int n = s.size();
	rep(i,n){
		if(islower(s[i])) {
			char c = s[i]-32;
			cout << c;
		}
		else {
			char c = s[i]+32;
			cout << c;
		}
	}
	return 0;
}