Medium · System Design
Random Pick Index
Given an integer array nums that may contain duplicates, answer repeated pick(target) calls: return an index i with nums[i] == target, chosen uniformly at random among all such indices. The target always occurs in nums.
Examples
Example 1
[1,2,3,3,3] target=3 draws=[0,0,1]Output: index 3
Example 2
[4,9,4,4] target=4 draws=[0,1,0]Output: index 3
Rebuild it in the studio
Open every published interview problem, solution, scene, and memory room free, with no account.