Problem:
Score : 300 points

Problem Statement

1000000000000001 dogs suddenly appeared under the roof of Roger's house, all of which he decided to keep. The dogs had been numbered 1 through 1000000000000001, but he gave them new names, as follows:

the dogs numbered 1,2,\cdots,26 were respectively given the names a, b, ..., z;

the dogs numbered 27,28,29,\cdots,701,702 were respectively given the names aa, ab, ac, ..., zy, zz;

the dogs numbered 703,704,705,\cdots,18277,18278 were respectively given the names aaa, aab, aac, ..., zzy, zzz;

the dogs numbered 18279,18280,18281,\cdots,475253,475254 were respectively given the names aaaa, aaab, aaac, ..., zzzy, zzzz;

the dogs numbered 475255,475256,\cdots were respectively given the names aaaaa, aaaab, ...;

and so on.

To sum it up, the dogs numbered 1, 2, \cdots were respectively given the following names:

a, b, ..., z, aa, ab, ..., az, ba, bb, ..., bz, ..., za, zb, ..., zz, aaa, aab, ..., aaz, aba, abb, ..., abz, ..., zzz, aaaa, ...

Now, Roger asks you:

"What is the name for the dog numbered N?"

Constraints

N is an integer.

1 \leq N \leq 1000000000000001

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer to Roger's question as a string consisting of lowercase English letters.

Sample Input 1

2

Sample Output 1

b

Sample Input 2

27

Sample Output 2

aa

Sample Input 3

123456789

Sample Output 3

jjddja

Solution in C++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i=0; i<(n); i++)
#define repi(i,a,b) for(int i = (a); i<= (b); i++)
#define repA(i,n) for(int i=n; i>=0; i--)
#define all(x) x.begin(),x.end()
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define sz(a) (int)(a.size())

typedef long long ll;
typedef long double ld;
const ll mod = 998244353;//1e9+7

vector<int> cnt[201],sp;

void pre() {

}

void solve() {
  ll n; cin>>n;
  string s = "";
  ll k = 26;
  while(n>0) {
    s = (char)('a'+ n%k - 1) + s;
    n = n/26;
  }
  cout<<s;
}

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0); cout.tie(0);
  #ifndef ONLINE_JUDGE
  freopen("input.txt","r",stdin);
  #endif
  int t = 1;
  pre();
  //cin>>t;
  rep(i,t)  {
    solve();
    cout<<'\n';
  }
  return 0;
}