#define _GLIBCXX_DEBUG
#define ll long long
#include <bits/stdc++.h>
using namespace std;
using Graph = vector<vector<int>>;

void print(auto a){
  cout << a;
}

void printL(auto a){
  cout << a << endl;
}

void fix(int n){
  cout << fixed << setprecision(n);
}

char CC(char c){
  if('a' <= c and c <= 'z') return c-'a'+'A';
  else return c-'A'+'a';
}

int main(){
  string S; cin >> S;
  string ans = "";
  for(int i = 0; i < (int)S.size(); i++){
    ans += CC(S[i]);
  }
  printL(ans);
}