#include <stdio.h>
int main(){
    //input
    char S[100+1];
    scanf("%s",S);

    //current password
    char cPass[100+1];
    for (int i = 0;i < 100+1;i++){
        if (S[i] != '\0'){
            if (S[i] < 97){
                cPass[i] = S[i]+32;
            }else{
                cPass[i] = S[i]-32;
            }
        }else{
            cPass[i] = '\0';
            break;
        }
    }
    
    //output
    printf("%s\n",cPass);
    return 0;
}