Given a non-empty array containing only positive integers, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal.继续阅读
Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target.继续阅读
A sequence of numbers is called a wiggle sequence if the differences between successive numbers strictly alternate between positive and negative. The first difference (if one exists) may be either positive or negative. A sequence with fewer than two elements is trivially a wiggle sequence.
LD 是个众所周知的糕富帅，从不把买切糕的钱当钱，只求量和品质，不惜价。但他还是会纠结买哪些切糕好，现假设切糕的价钱有 5 种分别为每两 2，2.5，3，3.5，4（百RMB），并且数量都假设为无限。现在告诉你 LD 一共有几百 RMB。请你告诉 LD 他一共有几种买切糕的方案（钱可以不花光，但一定要买，不花钱 LD 会不开心的）。
We are playing the Guess Game. The game is as follows:
I pick a number from 1 to n. You have to guess which number I picked.
Every time you guess wrong, I’ll tell you whether the number I picked is higher or lower.
However, when you guess a particular number x, and you guess wrong, you pay $x. You win the game when you guess the number I picked.
n = 10, I pick 8.
First round: You guess 5, I tell you that it’s higher. You pay 5. Second round: You guess 7, I tell you that it’s higher. You pay5.Secondround:Youguess7,Itellyouthatit
Third round: You guess 9, I tell you that it’s lower. You pay $9.
Game over. 8 is the number I picked.
You end up paying 5 +5+7 + 9 =9=21.
Given a particular n ≥ 1, find out how much money you need to have to guarantee a win.
Given a set of distinct positive integers, find the largest subset such that every pair (Si, Sj) of elements in this subset satisfies:
Si % Sj = 0 or Sj % Si = 0.
If there are multiple solutions, return any subset is fine.继续阅读
Given a non-empty 2D matrix matrix and an integer k, find the max sum of a rectangle in the matrix such that its sum is no larger than k.
Input: matrix = [[1,0,1],[0,-2,3]], k = 2
Explanation: Because the sum of rectangle [[0, 1], [-2, 3]] is 2,
and 2 is the max number no larger than k (k = 2).
The rectangle inside the matrix must have an area > 0.
What if the number of rows is much larger than the number of columns?