import sys
input = sys.stdin.readline
mod = 998244353

N = int(input())
x, y = divmod(N - 1, 36)
AB = []
for a in range(1, 10):
    for b in range(a+1, 10):
        AB.append((a, b))

aa, bb = AB[y]
print(str(aa) + str(bb) * (x + 1))