# -*- coding: utf-8 -*-
import sys,copy,math,heapq,itertools as it,fractions,re,bisect,collections as coll

def comb(n, r):
    res = 1
    for i in xrange(r):
        res *= n - i
    for i in xrange(1, r + 1):
        res /= i
    return res

ans = 0
N = int(raw_input())
#3は5n個、5は3m個。1桁目は必ず5
for k in xrange(3, 26):
    s = 0
    f = []
    for i in xrange(3, k + 1, 3):
        j = k - i
        cnt = comb(j + i - 1, i - 1)
        s += cnt
        f.append(i)
    if N > s:
        N -= s
    else:
        tmp = []
        for i in f:
            j = k - i
            for three in it.combinations(xrange(k - 1), j):
                num = ["5"] * k
                for l in three: num[l] = "3"
                tmp.append(int("".join(num)))
        tmp.sort()
        ans = tmp[N - 1]
        break
    if ans > 0: break
print ans