#include <bits/stdc++.h> using namespace std; int main() { char chr[81]; gets(chr); for(int i = 0;chr[i] != '\0';i++) { if(chr[i] >='A' && chr[i] <= 'Z') { chr[i] += 32; } else if(chr[i] >= 'a' && chr[i] <= 'z') { chr[i] -= 32; } } puts(chr); return 0; }