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题目描述

在一个二维数组中（每个一维数组的长度相同），每一行都按照从左到右递增的顺序排序，每一列都按照从上到下递增的顺序排序。请完成一个函数，输入这样的一个二维数组和一个整数，判断数组中是否含有该整数。

题目链接： https://www.nowcoder.com/practice/abc3fe2ce8e146608e868a70efebf62e

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Description

Koko loves to eat bananas. There are N piles of bananas, the i-th pile has piles[i] bananas. The guards have gone and will come back in H hours.

Koko can decide her bananas-per-hour eating speed of K. Each hour, she chooses some pile of bananas, and eats K bananas from that pile. If the pile has less than K bananas, she eats all of them instead, and won’t eat any more bananas during this hour.

Koko likes to eat slowly, but still wants to finish eating all the bananas before the guards come back.

Return the minimum integer K such that she can eat all the bananas within H hours.

题目链接：https://leetcode.com/problems/koko-eating-bananas/

Difficulty: medium

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Description

A robot on an infinite grid starts at point (0, 0) and faces north. The robot can receive one of three possible types of commands:

  • -2: turn left 90 degrees
  • -1: turn right 90 degrees
  • 1 <= x <= 9: move forward x units

Some of the grid squares are obstacles.

The i-th obstacle is at grid point (obstacles[i][0], obstacles[i][1])

If the robot would try to move onto them, the robot stays on the previous grid square instead (but still continues following the rest of the route.)

Return the square of the maximum Euclidean distance that the robot will be from the origin.

题目链接：https://leetcode.com/problems/walking-robot-simulation/

Difficulty: easy

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Description

A sequence X_1, X_2, …, X_n is fibonacci-like if:

  • n >= 3
  • X_i + X_{i+1} = X_{i+2} for all i + 2 <= n

Given a strictly increasing array A of positive integers forming a sequence, find the length of the longest fibonacci-like subsequence of A. If one does not exist, return 0.

(Recall that a subsequence is derived from another sequence A by deleting any number of elements (including none) from A, without changing the order of the remaining elements. For example, [3, 5, 8] is a subsequence of [3, 4, 5, 6, 7, 8].)

题目链接：https://leetcode.com/problems/length-of-longest-fibonacci-subsequence/

Difficulty: medium

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Description

Consider all the leaves of a binary tree. From left to right order, the values of those leaves form a leaf value sequence.

https://s3-lc-upload.s3.amazonaws.com/uploads/2018/07/16/tree.png

For example, in the given tree above, the leaf value sequence is (6, 7, 4, 9, 8).

Two binary trees are considered leaf-similar if their leaf value sequence is the same.

Return true if and only if the two given trees with head nodes root1 and root2 are leaf-similar.

题目链接：https://leetcode.com/problems/leaf-similar-trees/

Difficulty: easy

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Description

A car travels from a starting position to a destination which is target miles east of the starting position.

Along the way, there are gas stations. Each station[i] represents a gas station that is station[i][0] miles east of the starting position, and has station[i][1] liters of gas.

The car starts with an infinite tank of gas, which initially has startFuel liters of fuel in it. It uses 1 liter of gas per 1 mile that it drives.

When the car reaches a gas station, it may stop and refuel, transferring all the gas from the station into the car.

What is the least number of refueling stops the car must make in order to reach its destination? If it cannot reach the destination, return -1.

Note that if the car reaches a gas station with 0 fuel left, the car can still refuel there. If the car reaches the destination with 0 fuel left, it is still considered to have arrived.

题目链接：https://leetcode.com/problems/minimum-number-of-refueling-stops/

Difficulty: hard

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