Prefix Sums

Prefix sums, also known as cumulative sums or partial sums, is a technique used in programming to efficiently calculate the sum of a subarray or a range of elements within an array. By precomputing the cumulative sum of elements, developers can quickly retrieve the sum of any subarray, making it a valuable optimization for algorithms involving range queries, data analysis, and dynamic programming, and is particularly useful in competitive programming and data-intensive applications.