随笔分类 - 算法&Leetcode
摘要：Implement the following operations of a stack using queues.push(x) -- Push element x onto stack.pop() -- Removes the element on top of the stack.top()...
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摘要：Given an index k, return the kth row of the Pascal's triangle.For example, given k = 3, Return [1,3,3,1]. Note: Could you optimize your algorithm to u...
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摘要：Given an integer n, return the number of trailing zeroes in n!.Note: Your solution should be in logarithmic time complexity.Credits:Special thanks to ...
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摘要：Given a non-negative number represented as an array of digits, plus one to the number.The digits are stored such that the most significant digit is at...
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摘要：You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping yo...
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摘要：Given a sorted array, remove the duplicates in place such that each element appear only once and return the new length.Do not allocate extra space for...
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摘要：Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root).For e...
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摘要：Given an array and a value, remove all instances of that value in place and return the new length.The order of elements can be changed. It doesn't mat...
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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 / \ ...
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摘要：Given a binary tree, determine if it is height-balanced.For this problem, a height-balanced binary tree is defined as a binary tree in which the depth...
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摘要：Implement the following operations of a queue using stacks.push(x) -- Push element x to the back of queue.pop() -- Removes the element from in front o...
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摘要：Given an integer, write a function to determine if it is a power of two.Credits:Special thanks to @jianchao.li.fighter for adding this problem and cre...
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摘要：Write an algorithm to determine if a number is "happy".A happy number is a number defined by the following process: Starting with any positive integer...
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摘要：You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you cli...
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摘要：Given a sorted linked list, delete all duplicates such that each element appear only once.For example, Given 1->1->2, return 1->2. Given 1->1->2->3->3...
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摘要：Reverse a singly linked list对于这种可以修改值的，把值逆序就可以了。。。。用vector存，然后逆序读。都忘了指针怎么赋值初始化了。*p=&head; 1 /** 2 * Definition for singly-linked list. 3 * struct Li...
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摘要：Given a roman numeral, convert it to an integer.Input is guaranteed to be within the range from 1 to 3999.题目虽短，但是难度还是在那里的。首先，我们需要明白罗马数字是怎么计数的，当你明白了这个就...
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摘要：Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.You may assume that the ...
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摘要：Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming weight).For example, the 32-bit i...
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摘要：Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the arr...
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