https://www.acmicpc.net/problem/1174
N = int(input())
ret = []
arr_num = []
def convertArrToInt(arr):
ret = ''
for i in arr:
ret += str(i)
return int(ret)
def dfs(pick, N):
if pick == 10:
ret.append(convertArrToInt(arr_num))
return
ret.append(convertArrToInt(arr_num))
for i in range(0, 9):
if arr_num[-1]>i:
arr_num.append(i)
dfs(pick+1,N)
arr_num.pop()
if N > 1023:
print(-1)
else:
for i in range(0,10):
arr_num = [i]
dfs(1,N)
ret.sort()
print(ret[N-1])
