Insert Interval

描述

Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary).

You may assume that the intervals were initially sorted according to their start times.

Example 1:Given intervals [1,3],[6,9], insert and merge [2,5] in as [1,5],[6,9].

Example 2:Given [1,2],[3,5],[6,7],[8,10],[12,16], insert and merge [4,9] in as [1,2],[3,10],[12,16].

This is because the new interval [4,9] overlaps with [3,5],[6,7],[8,10].

分析

无

代码

  1. struct Interval {
  2.     int start;
  3.     int end;
  4.     Interval() : start(0), end(0) { }
  5.     Interval(int s, int e) : start(s), end(e) { }
  6. };
  8. // Insert Interval
  9. // 时间复杂度O(n)，空间复杂度O(1)
  10. public class Solution {
  11.     public List<Interval> insert(List<Interval> intervals, Interval newInterval) {
  12.         for (int i = 0; i < intervals.size();) {
  13.             final Interval cur = intervals.get(i);
  14.             if (newInterval.end < cur.start) {
  15.                 intervals.add(i, newInterval);
  16.                 return intervals;
  17.             } else if (newInterval.start > cur.end) {
  18.                 ++i;
  19.                 continue;
  20.             } else {
  21.                 newInterval.start = Math.min(newInterval.start, cur.start);
  22.                 newInterval.end = Math.max(newInterval.end, cur.end);
  23.                 intervals.remove(i);
  24.             }
  25.         }
  26.         intervals.add(newInterval);
  27.         return intervals;
  28.     }
  29. }

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原文: https://soulmachine.gitbooks.io/algorithm-essentials/content/java/simulation/insert-interval.html