#include<bits/stdc++.h> using namespace std; int main() { string s; cin>>s; for(int i=0;i<s.size();i++) { if(s[i]>='A'&&s[i]<='Z') { s[i]+=32; continue; } if(s[i]>='a'&&s[i]<='z') { s[i]-=32; continue; } } cout<<s; }