0665-non-decreasing-array.go

func checkPossibility(nums []int) bool {
	changed := false

	for i := 0; i < len(nums)-1; i++ {
		if nums[i] <= nums[i+1] {
			continue
		}
		if changed {
			return false
		}
		if i == 0 || nums[i+1] >= nums[i-1] {
			nums[i] = nums[i+1]
		} else {
			nums[i+1] = nums[i]
		}

		changed = true
	}

	return true
}