Sort Array by increasing Frequency

In this class, We discuss Sort Array by increasing Frequency.

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Question:

Given an array of integer values.

Sort the array in increasing order based on the Frequency of numbers.

If two numbers have the same Frequency, we need to arrange them in decreasing order.

Example:

Input: [2, 1, 2, 5, 7, 1, 7, 7]

Output: [5, 2, 2, 1, 1, 7, 7, 7,]

Logic:

Our last class used a hash table to maintain the element and element count.

The same is used in this example.

Once the hash table is created, sort the elements based on the Frequency.

One should understand using the sorted function in Python to sort the elements based on Frequency.

The step-by-step explanation is provided in the video.

Code: