Scribbling

How does one can find the number of pairs in an array that satisfies the below condition? : lower

Several solutions and short analysis of each one. 1. List + Binary Search The most straightforward solution, however, time complexity is O(N**2). class Solution: def countSmaller(self, nums: List[int]) -> List[int]: from bisect import insort, bisect_left arr = [] count = [] for i in range(len(nums) - 1, -1, -1): num = nums[i] idx = bisect_left(arr, num) count.append(idx) insort(arr, num) return ..