Given a binary array nums and an integer goal, return the number of subarrays with a sum equal to goal. A subarray is a contiguous part of

Given an integer array nums and an integer k, return the total number of subarrays in nums whose sum is equal to k. A subarray is a

Given an integer array nums, find the middle index in array, middleIndex. Note that you must find the leftmost middle index in nums array.

Given the head of singly linked list, return true if it is a palindrome, false otherwise. A palindrome is a sequence that reads the same for

Given the head node of a linked list, return the node where the cycle starts. If cycle does not exist, return null. Do not modify the linked

Given the head node of a singly linked list, determine if the linked list has a cycle in it. A linked list has a cycle if some node in the