Leetcode 57. Insert Interval

原题：

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]

.

解决方法：
很有意思的一道题。直接从原数值中取出区间，

- 如果该区间跟新区间有重叠，将该区间合并到新区间上；

- 如果新区间在该区间的前面，则先后插入新区间 和该区间；

- 如果该区间跟新区间不重叠，则直接加入到结果集中。

代码：

vector<Interval> insert(vector<Interval>& intervals, Interval newInterval) {
int n = intervals.size();
bool inserted = false;
vector<Interval> res;
for(auto i: intervals){
if (inserted){
res.push_back(i);
continue;
}
if (i.end < newInterval.start){
res.push_back(i);
}
else if (i.start > newInterval.end){
res.push_back(newInterval);
inserted = true;
res.push_back(i);
}else{
newInterval.start = min(newInterval.start, i.start);
newInterval.end = max(newInterval.end, i.end);
}
}

if (!inserted)
res.push_back(newInterval);

return res;
}