LeetCode-in-All
56. Merge Intervals
Medium
Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input.
Example 1:
Input: intervals = [[1,3],[2,6],[8,10],[15,18]]
Output: [[1,6],[8,10],[15,18]]
Explanation: Since intervals [1,3] and [2,6] overlap, merge them into [1,6].
Example 2:
Input: intervals = [[1,4],[4,5]]
Output: [[1,5]]
Explanation: Intervals [1,4] and [4,5] are considered overlapping.
Constraints:
1 <= intervals.length <= 104intervals[i].length == 20 <= starti <= endi <= 104
Solution
import "sort"
func merge(intervals [][]int) [][]int {
sort.Slice(intervals, func(i, j int) bool { return intervals[i][0] < intervals[j][0] })
res := [][]int{intervals[0]}
for i, j := 0, 1; j < len(intervals); j++ {
if res[i][1] >= intervals[j][0] {
res[i] = []int{res[i][0], max(res[i][1], intervals[j][1])}
} else {
res = append(res, intervals[j])
i++
}
}
return res
}