3sum With Multiplicity, is a LeetCode problem. In this post we will see how we can solve this challenge in C++

Problem Description

Given an integer array A, and an integer target, return the number of tuples i, j, k such that i < j < k and A[i] + A[j] + A[k] == target.

As the answer can be very large, return it modulo 10^9 + 7.

Example 1:

Input: A = [1,1,2,2,3,3,4,4,5,5], target = 8 Output: 20 Explanation: Enumerating by the values (A[i], A[j], A[k]): (1, 2, 5) occurs 8 times; (1, 3, 4) occurs 8 times; (2, 2, ....

You can find the full details of the problem 3Sum With Multiplicity at LeetCode

Solution: Please check the main.cpp snippet for the solution.

This solution originally posted at: Github by @kamyu104