It seems like the year of 2013 came only yesterday. Do you know a curious fact? The year of 2013 is the first year after the old 1987 with only distinct digits.

Now you are suggested to solve the following problem: given a year number, find the minimum year number which is strictly larger than the given one and has only distinct digits.
The single line contains integer *y* (1000 ≤ *y* ≤ 9000) — the year number.
import math
year = int(input())
a = math.trunc(year/1000)
b = math.trunc(year/100) - a*10
c = math.trunc(year/10)  - b*10 - a*100
d = year - a*1000 - b*100 - c*10
while True:
    if a != b and a!=c and a!=d and b!=c and b!=d and c!=d:
        print(year)
        break
    year += 1
