[LeetCode] Insert Interval

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].

先把要插入的区间放到最后，再排序，然后就跟上题一一模一样了。

/**
 * Definition for an interval.
 * struct Interval {
 *     int start;
 *     int end;
 *     Interval() : start(0), end(0) {}
 *     Interval(int s, int e) : start(s), end(e) {}
 * };
 */
 
bool cmp(const Interval &a, const Interval &b) {
    return a.start < b.start;
}

class Solution {
public:
    vector<Interval> insert(vector<Interval> &intervals, Interval newInterval) {
        int pos = 0, cnt = 0;
        intervals.push_back(newInterval);
        sort(intervals.begin(), intervals.end(), cmp);
        for (int i = 1; i < intervals.size(); ++i) {
            if (intervals[pos].end >= intervals[i].start) {
                ++cnt;
                if (intervals[pos].end < intervals[i].end) {
                    intervals[pos].end = intervals[i].end;
                }
            } else {
                ++pos;
                intervals[pos].start = intervals[i].start;
                intervals[pos].end = intervals[i].end;
            }
        }
        intervals.resize(intervals.size()-cnt);
        return intervals;
    }
};