#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ char a; cin>>a; if(a>='A'&&a<='Z') { cout<<(char)(a+32)<<endl; }else{ cout<<(char)(a-32)<<endl; } return 0; }