【题目】
Given a linked list, remove the nth node from the end of list and return its head.
For example,
Given linked list: 1->2->3->4->5, and n = 2.
After removing the second node from the end, the linked list becomes 1->2->3->5.
Note:
Given n will ...
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其他好文 时间:
2014-05-18 18:48:03
阅读次数:
269
题目:给定一个数组和一个目标值,返回所有不重复的3元组,每个元组的和等于目标值,且元组中,各元素按飞递减顺序。
先对其进行排序,在利用2sum,在2sum中,要求和为0,这里可以将数组中的元素的相反数作为和,找到另外两个数,那么三者的和为0。
在2sum中,经过排序后,总的时间复杂度是排序算法的复杂度占主导O(NlogN),在查找时是遍历数组,复杂度为O(n)。那么在3sum中,首先进行排序,...
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其他好文 时间:
2014-05-18 14:02:28
阅读次数:
249
Leetcode 151题 Reverse Words in a String...
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其他好文 时间:
2014-05-18 10:51:21
阅读次数:
243
【题目】
Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution.
For example, given array S = {...
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其他好文 时间:
2014-05-18 10:37:57
阅读次数:
269
【题目】
Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
The brackets must close in the correct order, "()" and "()[]{}" are all valid but "(]" and "([)]" are not.
【题意】
判断给定的字符串是否是合法的...
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其他好文 时间:
2014-05-18 10:08:11
阅读次数:
327
【题目】
Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
For example, given n = 3, a solution set is:
"((()))", "(()())", "(())()", "()(())", "()()()"
【题意】
给定n对括号,输出所有可行的括号组合字符串。所谓合法,就是可以Valid Pare...
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其他好文 时间:
2014-05-18 09:06:41
阅读次数:
266
【题目】
Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.
Note:
Elements in a quadruplet (a,b,c,d) must be in non-descending ord...
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其他好文 时间:
2014-05-18 08:46:04
阅读次数:
227
【题目】
Given a digit string, return all possible letter combinations that the number could represent.
A mapping of digit to letters (just like on the telephone buttons) is given below.
Input:Digit string "23"
Output: ["ad", "ae", "af", "bd", "be", "bf",...
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其他好文 时间:
2014-05-18 07:30:12
阅读次数:
340
对于本题,想到一个中序遍历后,判别是否为回文串的方法,却WA多次
class Solution {
public:
vector vectorValue;
void inOrder(TreeNode* root)
{
if(root!=NULL)
{
inOrder(root->left);...
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其他好文 时间:
2014-05-18 06:38:58
阅读次数:
294
3SumClosest
Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution....
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其他好文 时间:
2014-05-18 05:57:48
阅读次数:
244