#include<stdio.h>

int main (void)

{

    int n, initial_n;

    scanf("%d", &n);

    initial_n = n; 

    char num[] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j'};

    char unit[] = {, , 'S', 'B', 'Q', 'W', 'S', 'B', 'Q', 'Y'};

    char result[]={}; 

    int i, last_i = n % ;

    int j = ;

    int count_n = ;

    while (n > ) {

        i = n % ;

        n /= ;

        count_n ++;

        if (i ==  && (count_n % ) > ) {

            if (last_i != ) {

                result[j++]  = num[i];

            }

        }

        if (count_n ==  && i ==  && initial_n < ) {

            result[j++] =  unit[count_n];

        }

        if (count_n >  && i != ) {

            result[j++] = unit[count_n];

        }

        if (i != ) {

            result[j++] = num[i];

        }

        last_i = i;

    }

    if (initial_n == ) {

        result[j++]  = num[i];

    } 

    for (j=j-; j>=; j--) {

        printf("%c", result[j]);

    }

    printf("\n");

    return ;

}