#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i = (a); i < (b); ++i)
#define REP(i,n) FOR(i,0,n)
#define sz(n) (int)(n).size()
using namespace std;
typedef long long ll;
typedef vector<int> VI;

int main() {
	string s;
	cin >> s;
	REP(i, sz(s)) {
		if (s[i] > 'Z') s[i] += 'A' - 'a';
		else s[i] -= 'A' - 'a';
	}
	cout << s << endl;
	return 0;
}