n = int(input())
ans = [[i,j] for i in range(1,9) for j in range(2,10) if i < j]
syou = n//36
amari = n%36
a=0
for i in range(syou+1):
  a = a*10+1
print(10**(syou+1)*ans[amari-1][0] + a*ans[amari-1][1])