#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<cstdio>

using namespace std;

char chgcase (char c)
{
    if (isupper(c))
    {
        return c + 0x20;
    }
    else
    {
        return c - 0x20;
    }
}


int main()
{
    string s;
    
    cin >> s;
    transform(s.begin(), s.end(), s.begin(), chgcase); 
    cout << s << endl;
            
}