#include<iostream> #include<string> using namespace std; int main() { char a[260]; cin>>a; for(int i=0;i<260;i++){ if(a[i]=='A') cout<<"T" ; if(a[i]=='T') cout<<"A" ; if(a[i]=='C') cout<<"G" ; if(a[i]=='G') cout<<"C" ; } return 0; }