include <bits/stdc++.h>

using namespace std;

int main() { int n; cin>>n; deque<string>hk; while(n!=0){ int x=n%13; if(x>=10){ if(x==10){ hk.push_front("A"); } if(x==11){ hk.push_front("B"); } if(x==12){ hk.push_front("C"); } } else{ string s=to_string(x); hk.push_front(s); } n=n/13; } while(!hk.empty()){ cout<<hk.front(); hk.pop_front(); } }