#include<bits/stdc++.h>
using namespace std;
int main(){
  int i;
  char a[81];
  gets(a);
  for(i=0;a[i]!='\0';i++){
  if(a[i]>='a'&&a[i]<='z'){
  a[i]=a[i]-32;}
  else if(a[i]>='A'&&a[i]<='Z') a[i]=a[i]+32;
}
  cout<<a;
return 0;
}
/**************************************************************
	Problem: 1182
	User: wtq001
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/