LeetCode91 Leetcode. Max Consecutive Ones Problem: Given a binary array, find the maximum number of consecutive 1s in this array. Example 1: Input: [1,1,0,1,1,1] Output: 3 Explanation: The first two digits or the last three digits are consecutive 1s. The maximum number of consecutive 1s is 3. Note: The input array will only contain 0 and 1. The length of input array is a positive integer and will not exceed 10,000 class Solution: def fi.. 2020. 6. 29. LeetCode. Sum Root to Leaf Numbers Problem: Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 which represents the number 123. Find the total sum of all root-to-leaf numbers. Note: A leaf is a node with no children. -Summary- Used recursive DFS. # Definition for a binary tree node. # class TreeNode: # def __init__(self, val=0, left=Non.. 2020. 6. 27. LeetCode. Min Stack Problem: Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the top element. getMin() -- Retrieve the minimum element in the stack. Example 1: -Summary- Use tuple to save the minimum value and the current value of the stack. class MinStack: def __ini.. 2020. 6. 26. LeetCode. Shuffle an Array Problem: Shuffle a set of numbers without duplicates. Example: // Init an array with set 1, 2, and 3. int[] nums = {1,2,3}; Solution solution = new Solution(nums); // Shuffle the array [1,2,3] and return its result. Any permutation of [1,2,3] must equally likely to be returned. solution.shuffle(); // Resets the array back to its original configuration [1,2,3]. solution.reset(); // Returns the ra.. 2020. 6. 24. LeetCode. Count Complete Tree Nodes Problem: Given a complete binary tree, count the number of nodes. Note: Definition of a complete binary tree from Wikipedia: In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as possible. It can have between 1 and 2h nodes inclusive at the last level h. Example: -Summary- Solve by recursion 1. if the root exists.. 2020. 6. 24. LeetCode.Single Number II Problem: Given a non-empty array of integers, every element appears three times except for one, which appears exactly once. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? Example 1: Input: [2,2,3,2] Output: 3 Example 2: Input: [0,1,0,1,0,1,99] Output: 99 -Summary- Solved by using dictionary. 1. for each numbe.. 2020. 6. 23. 이전 1 2 3 4 5 6 ··· 16 다음
