1 #include <iostream>
 2 #include <iomanip>
 3 #include <iostream>
 4 #include <cmath>
 5 #include <string.h>
 6 #include <stdio.h>
 7 using namespace std;
 8 
 9 int main()
10 {
11     char str[256];
12     char str2[256] = {};
13     cin>>str;
14     int maxlen = strlen(str);
15     // cout<<maxlen;
16     for(int i=0;i<maxlen;i++)
17     {
18         if(str[i] == 'A')
19             str2[i] = 'T';
20         else if(str[i] == 'T')
21             str2[i] = 'A';
22         else if (str[i] == 'G')
23             str2[i] = 'C';
24         else if(str[i] == 'C')
25             str2[i] = 'G';
26     }
27     cout<<str2<<endl;
28 }