https://leetcode.com/problems/employees-earning-more-than-their-managers/ 181. Employees Earning More Than Their Managers Total Accepted: 27138 Total Submissions: 76486 Difficulty: Easy Contributors: Admin The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id. +—-+——-+——–+———–+ | Id | Name | Salary | ManagerId | +—-+——-+——–+———–+ | 1 …
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180. Consecutive Numbers Total Accepted: 12576 Total Submissions: 52571 Difficulty: Medium Contributors: Admin Write a SQL query to find all numbers that appear at least three times consecutively. +—-+—–+ | Id | Num | +—-+—–+ | 1 | 1 | | 2 | 1 | | 3 | 1 | | 4 | 2 | …
https://leetcode.com/problems/rank-scores/ 178. Rank Scores Total Accepted: 13824 Total Submissions: 58154 Difficulty: Medium Contributors: Admin Write a SQL query to rank scores. If there is a tie between two scores, both should have the same ranking. Note that after a tie, the next ranking number should be the next consecutive integer value. In other words, there …
346. Moving Average from Data Stream Total Accepted: 11701 Total Submissions: 20717 Difficulty: Easy Contributors: Admin Given a stream of integers and a window size, calculate the moving average of all integers in the sliding window. For example, MovingAverage m = new MovingAverage(3); m.next(1) = 1 m.next(10) = (1 + 10) / 2 m.next(3) = …
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163. Missing Ranges Total Accepted: 19465 Total Submissions: 66232 Difficulty: Medium Contributors: Admin Given a sorted integer array where the range of elements are in the inclusive range [lower, upper], return its missing ranges. For example, given [0, 1, 3, 50, 75], lower = 0 and upper = 99, return ["2", "4->49", "51->74", "76->99"]. …
388. Longest Absolute File Path Total Accepted: 11837 Total Submissions: 35565 Difficulty: Medium Contributors: Admin Suppose we abstract our file system by a string in the following manner: The string "dir\n\tsubdir1\n\tsubdir2\n\t\tfile.ext" represents: dir subdir1 subdir2 file.ext The directory dir contains an empty sub-directory subdir1 and a sub-directory subdir2 containing a file file.ext. The string "dir\n\tsubdir1\n\t\tfile1.ext\n\t\tsubsubdir1\n\tsubdir2\n\t\tsubsubdir2\n\t\t\tfile2.ext" …
Let’s say we have predictor variables (features) denoted as $latex X \in \mathbb{R}^n$ and response variable (label) $latex y$ whose underlying random variable is $latex Y$. If we want to fit an Ordinary Least Square (OLS) regression such that $latex y=WX+\epsilon$ where $latex \epsilon$ is an error term, then we have the following assumptions: strict exogenous: $latex E(\epsilon|X)=0$ …
https://leetcode.com/problems/house-robber/ 198. House Robber Total Accepted: 101581 Total Submissions: 275668 Difficulty: Easy Contributors: Admin 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 you from robbing each of them is that adjacent houses have security system connected and it …
https://leetcode.com/problems/binary-tree-longest-consecutive-sequence/ Given a binary tree, find the length of the longest consecutive sequence path. The path refers to any sequence of nodes from some starting node to any node in the tree along the parent-child connections. The longest consecutive path need to be from parent to child (cannot be the reverse). For example, 1 \ …
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70. Climbing Stairs Total Accepted: 139063 Total Submissions: 363734 Difficulty: Easy Contributors: Admin 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 climb to the top? Code from math import sqrt …