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 has_distinct_year(year_str):
    return len(set(year_str)) == len(year_str)

def beautiful_year(y):
    while True:
        y = str(int(y) + 1)
        if has_distinct_year(y):
            return y
        
def main():
    y = "1987"
    result = beautiful_year(y)
    print(result)
    
if __name__ == "__main__":
    main()