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 fo(i,a,n) for(i=a;i<n;i++)
#define ll long long
#define deb(x) cout << #x << "=" << x << endl
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
#define clr(x) memset(x, 0, sizeof(x))
#define sortall(x) sort(all(x))
#define sortrev(x) sort(all(x),greater<int>())
#define pi 3.1415926535897932384626

typedef pair<int,int> pii;
typedef pair<ll, ll> pl;
typedef vector<int>	vi;
typedef vector<ll>	vl;
typedef vector<pii>	vpii;
typedef vector<pl>	vpl;
typedef vector<vi>	vvi;
typedef vector<vl>	vvl;


const int mod = 100000007;
const int inf = 100000005;
const int N = 3e5, M = N;
ll i,j,n,m;


void solve() {
    ll n;
    cin>>n;
    
    string ans = "";
    while(n) {
        char c =(char)(n%26 + 96);
        if(n%26==0) ans+='z';
        else ans+=c;
        n/=26;
    }
    reverse(all(ans));
    cout<<ans<<"\n";
}


int main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    int t = 1;
    //cin >> t;
    while(t--) {
      solve();
    }

    return 0;
}