#include "bits/stdc++.h"
using namespace std;

int main() {
	string S;
	cin >> S;
	for (int i = 0; i < S.size(); i++) {
		int X = S[i];
		if (X <= 96) X += 32;
		else X -= 32;
		char C = X;
		cout << C;
	}
	cout << endl;
}