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 Python (3.8.2) (judge verdict: Runtime Error)

import numpy as np

N = int(input())
N_if = N
alf = ['0','a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']

data = []
count = 1
while(1):
  N_if -= 26**count
  if N_if < 0:
    #count += 1
    break
  count +=1
#print(count)   
N_if += 26**count

#print(N_if)

result = []
number = 1
for i in range(count):
  result.append(number)
  
#print(result)
while(1):
  q, mod = divmod(N_if, 26)
  data.append(mod)
  if q<27 :
    if q==0:
      data.append(q)
      data.append(100)
      break
    else:
      data.append(q)
      break
  N_if = q
answer = np.zeros(len(result),dtype = int)
#print(data)

for i in range(len(result)):
  answer[i] = int(data[len(result)-i-1] + result[i])
#print(answer)

answer[len(answer)-1] = answer[len(answer)-1]-1
#print(answer)
x = ''
if answer[0] >= 100:
  for i in range(len(answer)):
    x += alf[26]
    
else:
  for i in range(len(answer)):
    x += alf[answer[i]]
print(x)