Solution: Merge Intervals

Author: obzva

merge-intervals/flynn.go

@@ -0,0 +1,41 @@
+/*
+Big O
+- N: 주어진 배열 intervals의 길이
+- Time complexity: O(NlogN)
+  - intervals를 start의 오름차순으로 정렬 -> O(NlogN)
+  - 반복문 -> O(N)
+  - O(NlogN + N) = O(NlogN)
+- Space complexity: O(N)
+  - 정답 배열의 크기 -> O(N)
+*/
+
+import "sort"
+
+func merge(intervals [][]int) [][]int {
+	sort.Slice(intervals, func(i, j int) bool {
+		return intervals[i][0] < intervals[j][0]
+	})
+	res := make([][]int, 0)
+	start := intervals[0][0]
+	end := intervals[0][1]
+	for i := 1; i < len(intervals); i++ {
+		curr := intervals[i]
+		if end >= curr[0] {
+			end = max(end, curr[1])
+		} else {
+			res = append(res, []int{start, end})
+			start = curr[0]
+			end = curr[1]
+		}
+	}
+	res = append(res, []int{start, end})
+	return res
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	} else {
+		return b
+	}
+}