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 (Clang 10.0.0) (judge verdict: Runtime Error)

#include<stdio.h>

int main()
{
  long long int N=0,Q=0;
  long long int a[200000],b[200000],c[200000];
  long long int sum[100000000];
  
  scanf("%lld%lld",&N,&Q);
  for(int i=0;i<N;i++)
  {
    scanf("%lld",&a[i]);
  };
  
  for(int i=0;i<Q;i++)
  {
    scanf("%lld%lld",&b[i],&c[i]);
  };
  
   for(int i=0;i<Q;i++){
    for(int j=1;j<Q;j++)
    {
      if(a[j]==b[j]){
        a[j]=c[j];
      };
    };
    sum[i]+=a[i];
    };
     
    for(int i=0;i<Q;i++)
    {
      printf("%lld",sum[i]);
    };
     
     return 0;
   };