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.
def is_distinct(year):
    return len(set(str(year))) == 4

def next_distinct_year(year):
    while True:
        year += 1
        if is_distinct(year):
            return year

def main():
    y = int(input())
    next_year = next_distinct_year(y)
    print(next_year)

if __name__ == "__main__":
    main()
