Solution Review: Problem Challenge 1

Count of Subset Sum (hard) #

Given a set of positive numbers, find the total number of subsets whose sum is equal to a given number ‘S’.

Example 1: #

Input: {1, 1, 2, 3}, S=4
Output: 3
The given set has '3' subsets whose sum is '4': {1, 1, 2}, {1, 3}, {1, 3}
Note that we have two similar sets {1, 3}, because we have two '1' in our input.

Example 2: #

Input: {1, 2, 7, 1, 5}, S=9
Output: 3
The given set has '3' subsets whose sum is '9': {2, 7}, {1, 7, 1}, {1, 2, 1, 5}

Basic Solution #

This problem follows the 0/1 Knapsack pattern and is quite similar to Subset Sum. The only difference in this problem is that we need to count the number of subsets, whereas in ...