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<stdio.h>
#include<math.h>

int main (void)
{
    int i;
    int  mod26[16];
    char name[16];
    int count=0;
    long long N;

    scanf("%lld",&N);

    for(i=0;i<16;i++){
        mod26[i]=N%26;
        N=N/26;

        //printf("N:%d\n",N);
        if(N==0){
            break;
        }
    }
    count=i+1;

//    for(i=0;i<count;i++){
//        printf("i%d:%d\n",i,mod26[i]);
//        printf("%c",name[count-i]);
//    }

    //ここまで完成
    if(mod26[count-1]==0){
        count--;
    }
    for(i=0;i<count;i++){
        name[i]='a'+mod26[count-1-i]-1;
        //printf("i%d:%d\n",i,mod26[i]);
        printf("%c",name[i]);
    }


    return 0;
}