Given a set of characters and their corresponding frequencies of occurrence, produce Huffman codes for each character such that the average code length is minimised. Return the average code length.

ReadDesign a matrix-like data structure that allows you to update elements and query submatrix sums efficiently.

ReadDesign an array-like data structure that allows you to update elements and query subarray sums efficiently.

ReadYou are given a binary tree in which each node contains an integer value. Find the number of paths that sum to a given value. The path does not need to start or end at the root or a leaf.

Read