#include<bits/stdc++.h>
#define endl '\n'
#define MAXN 100000
using namespace std;

int main()
{
    string tmp;
    char ch;

    while(cin >> ch)
    {
        if(islower(ch)) tmp += toupper(ch);
        else tmp += tolower(ch);
    }

    cout << tmp << endl;
    return 0;
}