Developer Documents LeetCode Daily Practice With HashMap Optimization Approach

A developer has begun publicly documenting their daily LeetCode problem-solving journey on DEV Community. The challenge involved counting pairs of equal elements within an array. Their initial approach used a brute-force comparison of every element against every other, resulting in higher time complexity. They then optimized the solution using a HashMap to track element frequencies, incrementally adding the count of previous occurrences to the result. The final solution achieved O(n) time complexity, a significant improvement over the brute-force method.