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Given a binary tree, find the leftmost value in the last row of the tree.Example 1:Input: 2 / \ 1 3Output:1Example 2: Input: 1 / \ 2 3

Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and return them as an array.Example:For num = 5

There are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car with an unlimited gas tank and it costs cost[i] of gas to travel from station i to it

吝啬SAT问题：给定一组子句（每个子句都是其中文字的析取）和整数k，求一个最多有k个变量为true的满足赋值——如果该赋值存在。证明吝啬问题是NP-完全问题。解题思路 1.什么是SAT问题 假设我们有这样一组子句: (a⋃b⋃c)⋂(a⋃b¯)⋂(b⋃c¯)(a¯⋂c)⋂(a¯⋃b¯⋃c¯) 我们需要做的就是找到a,b,c的取值（true or false）使得该表达式的结果是true,假设

A sequence of number is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elements is the same.For example, these are arithmetic sequence:1,

Same TreeGiven two binary trees, write a function to check if they are equal or not.Two binary trees are considered equal if they are structurally identical and the nodes have the same value.解题思路： 给定两

Given an array of integers, every element appears twice except for one. Find that single one.Note: Your algorithm should have a linear runtime complexity. > Could you implement it without using extra

1单链表的读取 声明一个指针P指向链表中的第一个结点，初始化j从1开始； 当jStatus GetElem(LinkList L, int i, ElemType *e){ LinkList p; p=L->next; int j=1; while(p && j<i){ p=p->next; ++j; } if(!p || j>i

选择排序—简单选择排序（Simple Selection Sort） 基本思想：在要排序的一组数中，选出最小（或者最大）的一个数与第1个位置的数交换；然后在剩下的数当中再找最小（或者最大）的与第2个位置的数交换，依次类推，直到第n-1个元素（倒数第二个数）和第n个元素（最后一个数）比较为止。简单选择排序的示例：操作方法：第一趟，从n 个记录中找出关键码最小的记录与第一个记录交换；第二趟，从第二个记

输入：hello world 输出： world hello#include <stdio.h>#include <string.h>int main(){char s[3000],c[1000][20]={0};//c[j]来储存单词，k是单词中的字母int i,j=0,k=0;gets(s);for(i=0; i<strlen(s); i++){if(s[i]==' '){

交换排序—冒泡排序（Bubble Sort） 基本思想：在要排序的一组数中，对当前还未排好序的范围内的全部数，自上而下对相邻的两个数依次进行比较和调整，让较大的数往下沉，较小的往上冒。即：每当两相邻的数比较后发现它们的排序与排序要求相反时，就将它们互换。算法的实现：#include<iostream>#include<string>using namespace std;void print

Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.Note: You can only move either down or right at any

In the computer world, use restricted resource you have to generate maximum benefit is what we always want to pursue. For now, suppose you are a dominator of m 0s and n 1s respectively. On the other

Given a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contains only nodes with keys less than the node’s key. The right

Given a collection of intervals, find the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.Note:You may assume the interval's end point is always bigger

Given a string s and a string t, check if s is subsequence of t.You may assume that there is only lower case English letters in both s and t. t is potentially a very long (length ~= 500,000) string, an

Given a positive integer n, break it into the sum of at least two positive integers and maximize the product of those integers. Return the maximum product you can get.For example, given n = 2, return 1

Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target.Example:nums = [1, 2, 3]target = 4The possible com

You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount. If that amount of money c

Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000.Example 1:Input:"bbbab"Output:4One possible longest palindromic subsequ

这周上课的内容主要是讲了分治算法 挑选的题目:在一个未排序的数组里面找到第K大的元素。Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.For example,Giv

题目要求Given two binary strings, return their sum (also a binary string).For example,a = "11"b = "1"Return "100"代码public class Solution { public String addBinary(String a, String b) { if(a=

Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, …) which sum to n.For example, given n = 12, return 3 because 12 = 4 + 4 + 4; given n = 13, return

基本思想：1）选择一个基准元素,通常选择第一个元素或者最后一个元素,2）通过一趟排序讲待排序的记录分割成独立的两部分，其中一部分记录的元素值均比基准元素值小。另一部分记录的 元素值比基准值大。3）此时基准元素在其排好序后的正确位置4）然后分别对这两部分记录用同样的方法继续进行排序，直到整个序列有序。快速排序是通常被认为在同数量级（O(nlog2n)）的排序方法中平均性能最好的。但若初始序列按关键码有