Given a list of 24-hour clock time points in "Hour:Minutes" format, find the minimum minutes difference between any two time points in the list.
Example 1:
Input: ["23:59","00:00"] Output: 1
Note:
The number of time points in the given list is at least 2 and won't exceed 20000.The input time is legal and ranges from 00:00 to 23:59. 找相隔最短，这里可以利用bucket法。新建大小24*60的boolean数组，按照h*60+m把所有时间转换成int型，对应的bucket设置为true。在遍历boolean数组，找相隔最短的true。最后要注意比较一下min和24 * 60 - last + first的大小。代码如下： public class Solution { public int findMinDifference(List<String> timePoints) { boolean[] times = new boolean[24 * 60]; for (String time: timePoints) { String[] t = time.split(":"); int h = Integer.parseInt(t[0]); int m = Integer.parseInt(t[1]); if (times[h * 60 + m]) { return 0; } times[h * 60 + m] = true; } int pre = -24 * 60, min = Integer.MAX_VALUE, first = 24 * 60, last = 0; for (int i = 0; i < times.length; i ++) { if (times[i]) { min = Math.min(min, i - pre); if (first >= i) { first = i; } last = i; pre = i; } } return Math.min(min, 24 * 60 - last + first); } }