Function insert0

insert_interval_57/solution.go:82–148

Note: good attempt with 152 / 154 test cases passed. This got messy. Tried to merge newInterval into intervals. Can do better!

(intervals [][]int, newInterval []int)

// Note: good attempt with 152 / 154 test cases passed.
// This got messy. Tried to merge newInterval into intervals. Can do better!
func insert0(intervals [][]int, newInterval []int) [][]int {
	if len(intervals) == 0 {
		return [][]int{newInterval}
	}

	// interval goes in front and doesn't merge at all
	if newInterval[1] < intervals[0][0] {
		return append([][]int{newInterval}, intervals...)
	}

	// interval goes in front and merges
	if newInterval[1] == intervals[0][0] {
		intervals[0][0] = newInterval[0]
		return intervals
	}

	// newInterval start is less than first interval start
	if newInterval[0] < intervals[0][0] {
		intervals[0][0] = newInterval[0]
		intervals[0][1] = int(math.Max(float64(newInterval[1]), float64(intervals[0][1])))
	}

	for i := 0; i < len(intervals); i++ {
		interval := intervals[i]

		// find where the start is less than the finish of interval
		if newInterval[0] <= interval[1] {
			// while newIntervals end is greater than starts of subsequent intervals
			j := i
			for j < len(intervals) {
				// insert in between j and j-1
				if i > 0 && intervals[j-1][1] < newInterval[0] && intervals[j][0] > newInterval[1] {
					return append(append(append([][]int{}, intervals[:j]...), newInterval), intervals[j:]...)
				}

				if newInterval[1] <= intervals[j][0] {
					break
				}

				j++
			}

			if j == len(intervals) {
				intervals[i][0] = int(math.Min(float64(intervals[i][0]),
					float64(newInterval[0])))
				intervals[i][1] = int(math.Max(float64(newInterval[1]),
					float64(intervals[len(intervals)-1][1])))
				intervals = intervals[0 : i+1]
			} else if newInterval[1] < intervals[j][0] {
				intervals[i][0] = int(math.Min(float64(intervals[i][0]),
					float64(newInterval[0])))
				intervals[i][1] = int(math.Max(float64(intervals[j-1][1]),
					float64(newInterval[1])))
				if j-i > 1 {
					intervals = append(append([][]int{}, intervals[0:j-1]...), intervals[j:]...)
				}
			} else if newInterval[1] <= intervals[j][0] {
				intervals[i][1] = intervals[j][1]