731. My Calendar II

731. My Calendar II

• 题目描述：Implement a MyCalendarTwo class to store your events. A new event can be added if adding the event will not cause a triple booking.

  Your class will have one method, book(int start, int end). Formally, this represents a booking on the half open interval [start, end), the range of real numbers x such that start <= x < end.

  A triple booking happens when three events have some non-empty intersection (ie., there is some time that is common to all 3 events.)

  For each call to the method MyCalendar.book, return true if the event can be added to the calendar successfully without causing a triple booking. Otherwise, return false and do not add the event to the calendar.

  Your class will be called like this:

  Example 1:

  MyCalendar();MyCalendar.book(10, 20); // returns trueMyCalendar.book(50, 60); // returns trueMyCalendar.book(10, 40); // returns trueMyCalendar.book(5, 15); // returns falseMyCalendar.book(5, 10); // returns trueMyCalendar.book(25, 55); // returns trueExplanation: The first two events can be booked.  The third event can be double booked.The fourth event (5, 15) can't be booked, because it would result in a triple booking.The fifth event (5, 10) can be booked, as it does not use time 10 which is already double booked.The sixth event (25, 55) can be booked, as the time in [25, 40) will be double booked with the third event;the time [40, 50) will be single booked, and the time [50, 55) will be double booked with the second event.

• 题目大意：729题的扩展，要求插入的3个区间，互相不能有交集。

• 思路：使用之前写好的MyCalendar,判断两两是否相交。

• 代码：

  package Array;import java.util.ArrayList;import java.util.List;import java.util.TreeMap;/*** @Author OovEver* @Date 2017/11/28 10:10*/public class Solution {  class MyCalendarTwo {      private List<int[]> books;      public MyCalendarTwo() {          books=new ArrayList<>();      }      public boolean book(int start, int end) {          MyCalendar overlaps = new MyCalendar();          for(int []b:books){              if (Math.max(b[0], start) < Math.min(b[1], end)){                  if (!overlaps.book(Math.max(b[0], start), Math.min(b[1], end))) return false; // overlaps overlapped              } // overlap exist          }          books.add(new int[]{ start, end });          return true;      }      private class MyCalendar{          List<int[]> books=new ArrayList<>();          public boolean book(int start,int end){              for(int []b:books){                  if(Math.max(b[0],start)<Math.min(b[1],end)) return false;              }              books.add(new int[]{start,end});              return true;          }      }  }}