package LeetCode_539 import java.util.* /** * 539. Minimum Time Difference * https://leetcode.com/problems/minimum-time-difference/ * Given a list of 24-hour clock time points in "HH:MM" format, return the minimum minutes difference between any two time-points in the list. Example 1: Input: timePoints = ["23:59","00:00"] Output: 1 Example 2: Input: timePoints = ["00:00","23:59","00:00"] Output: 0 Constraints: 1. 2 <= timePoints <= 2 * 10^4 2. timePoints[i] is in the format "HH:MM". * */ class Solution { /* * solution: PriorityQueue, change time into num then insert into minHeap and calculate the min diff of any two elements. * Time:O(nlogn), Space:O(n) * */ fun findMinDifference(timePoints: List<String>): Int { val minHeap = PriorityQueue<Int>() for (time in timePoints) { val times = time.split(":") val h = times[0].toInt() val m = times[1].toInt() //insert minutes minHeap.add(h * 60 + m) } var result = Int.MAX_VALUE val first = minHeap.poll() var cur = first while (minHeap.isNotEmpty()) { val next = minHeap.poll() //compare between any two times result = Math.min(result, next - cur) cur = next } /* * because need compare between any two times, also need compare the first and last, because the different is 24 hours, so the first time need add 24*60 * */ result = Math.min(result, 24*60+first-cur) return result } }