#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <iomanip>
#include <cmath>
#include <functional>
using namespace std;
#define diff(x,y) ((x > y) ? (x - y) : (y - x))
#define us(x) (x > 0) ? x : x * -1
#define lli long long int

int main() {
	string str;
	cin >> str;
	for (int i = 0; i < str.size(); i++) {
		if (str[i] <= 'Z')	str[i] += 32;
		else				str[i] -= 32;
	}
	cout << str << endl;
	return 0;
}