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Heap

Find Median from Data Stream

hard

max (21)341224132;341225102;21365487109
Count: 10
abcValid triangle requires:a + b > c AND a + c > b AND b + c > a(every pair must sum to more than the third side)3511SOURCE23211SOURCE23UNREACHABLE$100$100$100$5000SRC123DST$100$100$1000SRC123DST01233141Threshold: 4Answer: 32 reachable01234231118Threshold: 2Answer: 01 reachable1102233321432263321
DESCRIPTION (inspired by Leetcode.com)

A live analytics dashboard starts with nums. New readings arrive in order in adds. After each incoming value is inserted, return the current median of all readings seen so far. If the count is even, the median is the average of the two middle values.

Example 1:

Inputs:

nums = [5, 2, 8]
adds = [3, 10, 4]

Output:

[4, 5, 4.5]

Building Intuition

Approach 1: Sort Every Time

Why That Hurts

What Do We Actually Need?

Building Toward Heaps

Approach 2: Split the Stream Into Two Heaps

Pseudocode

Walkthrough

Solution

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On This Page

Building Intuition

Approach 1: Sort Every Time

Why That Hurts

What Do We Actually Need?

Building Toward Heaps

Approach 2: Split the Stream Into Two Heaps

Pseudocode

Walkthrough

Solution

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