def f(n):

    alphabets = "abcdefghijklmnopqrstuvwxyz"



    s = ""

    while n > 0:

        n, mod = divmod(n, 26)

        if mod == 0:

            s += 'z'

            n -= 1

        else:

            s += alphabets[mod - 1]

    

    return s[::-1]



print((f(int(eval(input())))))
n = int(eval(input()))

a = "abcdefghijklmnopqrstuvwxyz"

s = ""

while n > 0:

    n, m = divmod(n, 26)



    if not m:

        n -= 1



    s = a[(m - 1) % 26] + s



print(s)
def f(n):
    alphabets = "abcdefghijklmnopqrstuvwxyz"
    s = ""
    while n > 0:
        n, mod = divmod(n, 26)
        if mod == 0:
            s += "z"
            n -= 1
        else:
            s += alphabets[mod - 1]
    return s[::-1]


print((f(int(eval(input())))))

n = int(eval(input()))
a = "abcdefghijklmnopqrstuvwxyz"
s = ""
while n > 0:
    n, m = divmod(n, 26)
    if not m:
        n -= 1
    s = a[(m - 1) % 26] + s
print(s)

-def f(n): -    alphabets = "abcdefghijklmnopqrstuvwxyz" -    s = "" -    while n > 0: -        n, mod = divmod(n, 26) -        if mod == 0: -            s += "z" -            n -= 1 -        else: -            s += alphabets[mod - 1] -    return s[::-1] - - -print((f(int(eval(input()))))) +n = int(eval(input())) +a = "abcdefghijklmnopqrstuvwxyz" +s = "" +while n > 0: +    n, m = divmod(n, 26) +    if not m: +        n -= 1 +    s = a[(m - 1) % 26] + s +print(s)