Given n items with size Ai, an integer m denotes the size of a backpack. How full you can fill this backpack?

In data structure Hash, hash function is used to convert a string(or any other type) into an integer smaller than hash size and bigger or equal to zero. The objective of designing a hash function is to "hash" the key as unreasonable as possible. A good hash function can avoid collision as less as...

Given an directed graph, a topological order of the graph nodes is defined as follow:

The size of the hash table is not determinate at the very beginning. If the total size of keys is too large (e.g. size >= capacity / 10), we should double the size of the hash table and rehash every keys. Say you have a hash table looks like below:

For a heap array A, A[0] is the root of heap, and for each A[i], A[i * 2 + 1] is the left child of A[i] and A[i * 2 + 2] is the right child of A[i].

首先，我们应该了解字典树的性质和结构，就会很容易实现要求的三个相似的功能：插入，查找，前缀查找。既然叫做字典树，它一定具有顺序存放26个字母的性质。另外，为了实现和区别全词查找和前缀查找，应该有一个标记。所以，在字典树的class里面，添加ch，exist和children三个参数。

Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors.

Given an integer array, find a subarray where the sum of numbers is zero. Your code should return the index of the first number and the index of the last number.

Given an integer matrix, find a submatrix where the sum of numbers is zero. Your code should return the coordinate of the left-up and right-down number.

Problem Calculate the a^n % b where a, b and n are all 32bit integers. Example For 2^31 % 3 = 2 For 100^1000 % 1000 = 0 Challenge O(logN) Note 应用求余公式: (a * b) % p = (a % p * b % p) % p使用分治法，不断分解a^n为a^(n/2)，最终的子问题就是求解a^1或者a^0的余数。唯一要注意的就是，若n为奇数，要将余...

Given an array with positive and negative integers. Re-range it to interleaving with positive and negative integers.

Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue.

Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.

Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.

Implement an algorithm to determine if a string has all unique characters.

Write a method anagram(s,t) to decide if two strings are anagrams or not.

Suppose a sorted array is rotated at some pivot unknown to you beforehand.

You are given an n x n 2D matrix representing an image.Rotate the image by 90 degrees (clockwise).

Given an array of integers, find two numbers such that they add up to a specific target number.

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.

Given n, how many structurally unique BSTs (binary search trees) that store values 1...n?

Merge two sorted (ascending) linked lists and return it as a new sorted list. The new sorted list should be made by splicing together the nodes of the two lists and sorted in ascending order.

Given a List 3->2->1->5->null and n = 2, return node whose value is 1.

You have two numbers represented by a linked list, where each node contains a single digit. The digits are stored in reverse order, such that the 1's digit is at the head of the list. Write a function that adds the two numbers and returns the sum as a linked list.

Given a list, rotate the list to the right by k places, where k is non-negative.

Given an array of strings, return all groups of strings that are anagrams.

Given an array and a value, remove all occurrences of that value in place and return the new length.

Given 1->3->2->0->null, return 0->1->2->3->null.

Given a linked list, remove the nth node from the end of list and return its head.

Given a directed graph, design an algorithm to find out whether there is a route between two nodes.