Merge Intervals_leetcode_go

Merge Intervals

题目：

Given a collection of intervals, merge all overlapping intervals.

Example 1:

Input: [[1,3],[2,6],[8,10],[15,18]]
Output: [[1,6],[8,10],[15,18]]
Explanation: Since intervals [1,3] and [2,6] overlaps, merge them into [1,6].
Example 2:

Input: [[1,4],[4,5]]
Output: [[1,5]]
Explanation: Intervals [1,4] and [4,5] are considerred overlapping.

思路：

• 按interval.Start排序。有重合则合并，无重合则加到结果集。
• 注意Interval要值拷贝。

解：

func merge(intervals []Interval) []Interval {
    res := make([]Interval, 0)
    if len(intervals) == 0 {
        return res
    }

    sort.Slice(intervals, func(i, j int) bool {
        if intervals[i].Start < intervals[j].Start {
            return true
        }
        return false
    })

    curRes := Interval{intervals[0].Start,intervals[0].End}
    for i := 1; i < len(intervals); i++ {
        if curRes.End >= intervals[i].Start {
            if intervals[i].End > curRes.End {
                curRes.End = intervals[i].End
            }
        } else {
            res = append(res, curRes)
            curRes = Interval{intervals[i].Start,intervals[i].End}
        }
    }
    res = append(res, curRes)
    return res
}