#include<bits/stdc++.h> using namespace std; int main(){ char a[505]; cin.getline(a,505); int len=strlen(a); for(int i=0;i<=len-1;i++){ if('A'<=a[i]&&a[i]<='Z'){ a[i]+=32; cout<<a[i]; } else if('a'<=a[i]&&a[i]<='z'){ a[i]-=32; cout<<a[i]; } else cout<<a[i]; } return 0; }