539. Minimum Time Difference

Example 1:

Input: ["23:59","00:00"]
Output: 1

Note:

1. The number of time points in the given list is at least 2 and won't exceed 20000.

1. The input time is legal and ranges from 00:00 to 23:59.

代码如下:

class Solution {
        public int findMinDifference(List<String> timePoints) {
            int mm = Integer.MAX_VALUE;
            List<Integer> list = new ArrayList<>();

            for(String str : timePoints){
                int hour = Integer.valueOf(str.substring(0, 2));
                int minute = Integer.valueOf(str.substring(3, 5));
                list.add(hour * 60 + minute);
            }

            Collections.sort(list, (Integer a, Integer b) -> a - b);

            for(int i = 1; i < list.size(); i++)
                mm = Math.min(mm, list.get(i) - list.get(i-1));

            return Math.min(mm, list.get(0) + 1440 - list.get(list.size()-1));
        }
    }