#include<bits/stdc++.h> using namespace std; string a,w,c="0123456789ABCDEF"; int main() { cin>>a; if(a.size()%4==3) a='0'+a; else if(a.size()%4==2) a="00"+a; else if(a.size()%4==1) a="000"+a; for(int i=0;i<a.size();i=i+4){ w=a.substr(i,4); cout<<c[(w[3]-'0')*1+(w[2]-'0')*2+(w[1]-'0')*4+(w[0]-'0')*8]; } return 0; } /************************************************************** Problem: 1294 User: zhuangsongyu Language: C++ Result: Accepted Time:8 ms Memory:2076 kb ****************************************************************/