C++

題目

Evaluate the value of an arithmetic expression in Reverse Polish Notation.

題目

You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security systems connected and it will automatically contact the police if two adjacent houses were broken into on the same night.

題目

Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.

題目

You are climbing a staircase. It takes n steps to reach the top.

Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?

題目

A path in a binary tree is a sequence of nodes where each pair of adjacent nodes in the sequence has an edge connecting them. A node can only appear in the sequence at most once. Note that the path does not need to pass through the root.

題目

Given the root of a binary tree, split the binary tree into two subtrees by removing one edge such that the product of the sums of the subtrees is maximized.

題目

Given the root of a binary tree, find the maximum value v for which there exist different nodes a and b where v = |a.val - b.val| and a is an ancestor of b.

題目

Consider all the leaves of a binary tree, from left to right order, the values of those leaves form a leaf value sequence.

題目

Given the head of a singly linked list, group all the nodes with odd indices together followed by the nodes with even indices, and return the reordered list.

題目

Given the head of a singly linked list, return the middle node of the linked list.

If there are two middle nodes, return the second middle node.