#include <iostream>
#include <vector>
#include <map>
#include<string>
#include<queue>
#include<math.h>
#define all(x) begin(x),end(x)
#define ll long long
#define P pair<int,int>
#define lP pait<ll,ll>
using namespace std;
int main() {
    string s;
    cin>>s;
    for(int i=0;i<s.size();i++){
        if(s[i]>96 and s[i]< 123) s[i]-=32;
        else s[i]+=32;
    }
    cout<<s<<endl;
    return 0;
}