2013年9月17日
LeetCode-Path Sum
摘要： Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ ... 阅读全文
posted @ 2013-09-17 11:19 懒猫欣 阅读(142) 评论(0) 推荐(0)
LeetCode-Valid Number
摘要： Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => trueNote: It is intended for the problem statement to be ambiguous. You should gather all requirements up front before 阅读全文
posted @ 2013-09-17 10:59 懒猫欣 阅读(136) 评论(0) 推荐(0)
2013年9月16日
LeetCode-First Missing Positive
摘要： Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space.class Solution {public: int firstMissingPositive(int A[], int n) { // Start typing your C/C++ solutio 阅读全文
posted @ 2013-09-16 21:02 懒猫欣 阅读(130) 评论(0) 推荐(0)
LeetCode-Symmetric Tree
摘要： Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).For example, this binary tree is symmetric: 1 / \ 2 2 / \ / \3 4 4 3 But the following is not: 1 / \ 2 2 \ \ 3 3 Note:Bonus points if you could solve it both recursively and itera... 阅读全文
posted @ 2013-09-16 18:40 懒猫欣 阅读(223) 评论(0) 推荐(0)
LeetCode-Same Tree
摘要： Given 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./** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * ... 阅读全文
posted @ 2013-09-16 18:15 懒猫欣 阅读(174) 评论(0) 推荐(0)
LeetCode-Maximum Depth of Binary Tree
摘要： Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node./** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x... 阅读全文
posted @ 2013-09-16 18:12 懒猫欣 阅读(171) 评论(0) 推荐(0)
LeetCode-Palindrome Number
摘要： Determine whether an integer is a palindrome. Do this without extra space.click to show spoilers.Some hints:Could negative integers be palindromes? (ie, -1)If you are thinking of converting the integer to string, note the restriction of using extra space.You could also try reversing an integer. Howe 阅读全文
posted @ 2013-09-16 14:54 懒猫欣 阅读(177) 评论(0) 推荐(0)
LeetCode-ZigZag Conversion
摘要： The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)P A H NA P L S I I GY I RAnd then read line by line: "PAHNAPLSIIGYIR"Write the code that will take a string 阅读全文
posted @ 2013-09-16 14:27 懒猫欣 阅读(173) 评论(0) 推荐(0)
LeetCode-Median of Two Sorted Arrays
摘要： There are two sorted arrays A and B of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)).class Solution {public: int FindKthElm(int A[],int bA,int eA,int B[],int bB,int eB,int k){ if(bA>eA){ return B[bB+k-... 阅读全文
posted @ 2013-09-16 12:11 懒猫欣 阅读(183) 评论(0) 推荐(0)
LeetCode-Convert Sorted Array to Binary Search Tree
摘要： Given an array where elements are sorted in ascending order, convert it to a height balanced BST./** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */class Solution {public: ... 阅读全文
posted @ 2013-09-16 02:27 懒猫欣 阅读(137) 评论(0) 推荐(0)