#include<iostream> #include<cstring> using namespace std; char a[256]; int main() { cin>>a; int c=strlen(a); for(int i=0;i<c;i++){ if(a[i]=='A'){ cout<<"T"; } if(a[i]=='T'){ cout<<"A"; } if(a[i]=='G'){ cout<<"C"; } if(a[i]=='C'){ cout<<"G"; } } return 0; }