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: Accepted)

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

#define FASTIO  ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define ll long long int
#define ld long double
#define vll vector<ll>
#define pll pair<ll,ll>
#define vl(p) vector<p>
#define w while
#define For(i,s,x) for(i=s;i<x;i++)
#define Fore(i,s,x) for(i=s;i<=x;i++)
#define FOR(i,x) for(i=0;i<x;i++)
#define Rof(i,s,x) for(i=s;i>=x;i--)
#define all(v) v.begin(),v.end()
#define it(r,v) for(auto r=v.begin();r!=v.end();r++)
#define pb push_back
#define in insert
#define sz size()
#define F first
#define S second
#define nl cout<<"\n"
#define pr(a) cout<<a<<" "
#define pr2(a,b) cout<<a<<" "<<b<<"\n"
#define pr3(a,b,c) cout<<a<<" "<<b<<" "<<c<<"\n"
#define mod 1000000007
const double PI = 3.141592653589793238;

int main()
{
	FASTIO;


        ll i,j,k,x,y,z,n,m,a,b,c,c1=1,c2=0,flag=0,sum=0;
        char ch;
        string s;

        cin>>n;
        vector<string>ss;
        while(n>0)
        {

            m=n%26;
            if(m==0)
                m=26;
            n=n-1;
            n=n/26;

            m=m+96;
            ch=m;
            s=ch;
            ss.push_back(s);

        }

        x=ss.size();
        for(i=x-1;i>=0;i--)
            cout<<ss[i];



}