#include <iostream>

int main(void){
  std::string s;
  int length;
  int x[100];
 
  std::cin >> s;
  const char* c = s.c_str();
  length = s.length();
  for(int i=0;i<length;i++){
    int j = (int)c[i];
    if(j>96){
      x[i]=j-32;
    }
    else{
      x[i]=j+32;
    }
    std::cout << (char)x[i];
  }
  std::cout << std::endl;
}