test.kt

class Solution {
    fun merge(intervals: Array<IntArray>): Array<IntArray> {

        if (intervals.size < 2) return intervals

        intervals.sortBy { it[0] }

        var index = 1
        val result = ArrayList<IntArray>()
        var merge: IntArray = intervals[0]
        var point: IntArray = intervals[1]

        while (true) {

            if (needMerge(merge, point)) {
                merge = merge(merge, point)

                if (index + 1 > intervals.lastIndex) {
                    result.add(merge)
                    break
                } else {
                    point = intervals[index+1]
                    index+=1
                }
            } else {
                result.add(merge)

                if (index  > intervals.lastIndex) {
                    break
                } else if (index + 1 > intervals.lastIndex) {
                    result.add(intervals[index])
                    break
                }

                merge = intervals[index ]
                point = intervals[index +1]
                index += 1
            }
        }
        return result.toTypedArray()
    }

    fun needMerge(input1: IntArray, input2: IntArray): Boolean {
        return input1[1] >= input2[0]
    }

    fun merge(input1: IntArray, input2: IntArray): IntArray {
        val end = if (input1[1] > input2[1]) input1[1] else input2[1]
        val merge = IntArray(2)
        merge[0] = input1[0]
        merge[1] = end
        return merge
    }

}