## 681.Next Closest Time

Given a time represented in the format "HH:MM", form the next closest time by reusing the current digits. There is no limit on how many times a digit can be reused.

You may assume the given input string is always valid. For example, "01:34", "12:09" are all valid. "1:34", "12:9" are all invalid.

Example 1:

``````Input:
"19:34"

Output:
"19:39"

Explanation:
The next closest time choosing from digits 1, 9, 3, 4, is 19:39, which occurs 5 minutes later.  It is not 19:33,
because this occurs 23 hours and 59 minutes later.
``````

Example 2:

``````Input:
"23:59"

Output:
"22:22"

Explanation:
The next closest time choosing from digits 2, 3, 5, 9, is 22:22.
It may be assumed that the returned time is next day's time since it is smaller than the input time numerically.
``````

Thoughts:

1. Brutally find all the digits increments (24*60), rank the time
2. Using time increments to find the closest time
``````class Solution(object):
def nextClosestTime(self, time):
"""
:type time: str
:rtype: str
"""
# turn the forward by one minute until time follows the same set
return min((t <= time, t)
for i in range(24 * 60)
for t in ['%02d:%02d' % divmod(i, 60)]
if set(t) <= set(time)) ;
``````