266.Palindrome Permutation

2021-09-18

Problem description:

Given a string s, return true if a permutation of the string could form a palindrome.

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1216.Valid Palindrome III

2021-09-18

Problem description:

Given a string s and an integer k, return true if s is a k-palindrome.

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691.Stickers to Spell Word

2021-09-17

Problem description:

We are given n different types of stickers. Each sticker has a lowercase English word on it.

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1891.Cutting Ribbons

2021-09-17

Problem description:

You are given an integer array ribbons, where ribbons[i] represents the length of the ith ribbon, and an integer k. You may cut any of the ribbons into any number of segments of positive integer lengths, or perform no cuts at all.

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986.Interval List Intersections

2021-09-17

Problem description:

You are given two lists of closed intervals, firstList and secondList, where firstList[i] = [starti, endi] and secondList[j] = [startj, endj]. Each list of intervals is pairwise disjoint and in sorted order.

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509.Fibonacci Number

2021-09-17

Problem description:

The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1. That is,

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408.Valid Word Abbreviation

2021-09-17

Problem description:

A string can be abbreviated by replacing any number of non-adjacent substrings with their lengths. For example, a string such as "substitution" could be abbreviated as (but not limited to):

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163. Missing Ranges

2021-09-17

Problem description:

You are given an inclusive range [lower, upper] and a sorted unique integer array nums, where all elements are in the inclusive range.

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536. Construct Binary Tree from String

2021-09-16

Problem description:

You need to construct a binary tree from a string consisting of parenthesis and integers.

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766. Toeplitz Matrix

2021-09-16

Problem description:

Given an m x n matrix, return true if the matrix is Toeplitz. Otherwise, return false.

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