Solving Random Pick with Blacklist in go. Please try yourself first to solve the problem and submit your implementation to LeetCode before looking into solution.

Problem Description

Given a blacklist B containing unique integers from [0, N), write a function to return a uniform random integer from [0, N) which is NOT in B.


  1. 1 <= N <= 1000000000
  2. 0 <= B.length < min(100000, N)
  3. [0, N) does NOT include N. See interval notation.

Example 1:

Output: [null,0,0,0]

Example 2:

Output: [null,1,1,1]

Example 3:

Output: [null,0,0,2]

Example 4:

Output: [null,1,3,1]

Explanation of Input Syntax:

The input is two lists: the subroutines called and their arguments. Solution's constructor has two arguments, N and the blacklist B. pick has no arguments. Arguments are always wrapped with a list, even if there aren't any.

See the full details of the problem Random Pick with Blacklist at LeetCode

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