n = int(input())
keta = n // 36 + 2
n = n % 36
cnt = 0
for i in range(1, 10):
    for j in range(i + 1, 10):
        if i != j:
            cnt += 1
            if cnt == n:
                ans = (i, j)
print(str(ans[0]) + str(ans[1]) * (keta - 1))