0703-kth-largest-element-in-a-stream.rb

# frozen_string_literal: true

# 703. Kth Largest Element in a Stream
# https://leetcode.com/problems/kth-largest-element-in-a-stream
# Easy

=begin
Design a class to find the kth largest element in a stream. Note that it is the kth largest element in the sorted order, not the kth distinct element.

Implement KthLargest class:

KthLargest(int k, int[] nums) Initializes the object with the integer k and the stream of integers nums.
int add(int val) Appends the integer val to the stream and returns the element representing the kth largest element in the stream.

Example 1:
Input
["KthLargest", "add", "add", "add", "add", "add"]
[[3, [4, 5, 8, 2]], [3], [5], [10], [9], [4]]
Output
[null, 4, 5, 5, 8, 8]

Explanation
KthLargest kthLargest = new KthLargest(3, [4, 5, 8, 2]);
kthLargest.add(3);   // return 4
kthLargest.add(5);   // return 5
kthLargest.add(10);  // return 5
kthLargest.add(9);   // return 8
kthLargest.add(4);   // return 8

Constraints:
1 <= k <= 104
0 <= nums.length <= 104
-104 <= nums[i] <= 104
-104 <= val <= 104
At most 104 calls will be made to add.
It is guaranteed that there will be at least k elements in the array when you search for the kth element.
=end

class KthLargest
=begin
    :type k: Integer
    :type nums: Integer[]
=end
  def initialize(k, nums)
    @max_size = k
    @data = nums.sort.reverse[0...k]
  end


=begin
    :type val: Integer
    :rtype: Integer
=end
  def add(val)
    if (i = @data.bsearch_index { |x| x < val })
      @data.insert(i, val)
    else
      @data.push(val)
    end
    @data.pop if @data.length > @max_size
    # @data.sort!{|a, b| b<=> a}
    @data.last
  end
end

# Your KthLargest object will be instantiated and called as such:
# obj = KthLargest.new(k, nums)
# param_1 = obj.add(val)