#include <iostream>
#include <string.h>
using namespace std;
int main(){
    char pass[100];
    cin>>pass;
    int i;
    for(i=0;i>=100;i++){
        if(pass[i]==0){
            break;
        }
        if(pass[i]<94){
          pass[i]+=32;  
        }else{
            pass[i]-=32;
        }
        
    }
    cout<<pass[i];
    
}