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leetcode-diaries

A journal to record the solution of the various Leetcode problems solved over the course of time.

Number of Good Pairs

Leetcode problem 1512; Difficulty: Easy

Problem Statement

Given an array of integers nums.

A pair (i,j) is called good if nums[i] == nums[j] and i < j.

Return the number of good pairs.

Constraints:

Example 1:

Input: nums = [1,2,3,1,1,3]

Output: 4

Explanation:

There are 4 good pairs (0,3), (0,4), (3,4), (2,5) 0-indexed.

Example 2:

Input: nums = [1,1,1,1]

Output: 6

Explanation:

Each pair in the array are good.

Example 3:

Input: nums = [1,2,3]

Output: 0

Submitted Solution

The implemented solution received the following rating on Leetcode:

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