leetcode--441--Arranging coins

Problem Description:

You have a total of n coins, you need to put them in a ladder shape, the K -line must have exactly the k coin.

Given a number n, find the total number of rows that can form a complete ladder row.

N is a non-negative integer and is within the range of a 32-bit signed integer.

Example 1:

n = 5 coins can be arranged in the following lines: ¤¤¤¤¤ returns 2 because the third line is incomplete.

Example 2:

n = 8 coins can be arranged in the following lines: ¤¤¤¤¤¤¤¤ returns 3 because the row is incomplete.

Method 1:

1 classsolution (object):2     defarrangecoins (self, n):3         """4 : Type N:int5 : Rtype:int6         """        7Low =08High =N9         Ten          whilelow<=High : Onemid = Int ((low+high)//2) A              -             ifmid* (mid+1)/2 <= N < (mid+1) * (mid+2)/2: -                 returnMid the             elifmid* (mid+1)/2 >N: -High = Mid-1 -             elif(mid+1) * (mid+2)/2 <=N: -Low = mid + 1

Amazing:

1 class solution (object): 2     def arrangecoins (self, n): 3          return Int (((8*n + 1) **0.5-1)/2)

Ditto:

class solution (Object):     def arrangecoins (self, N):         """         : Type n:int        : Rtype:int        "        " "= Int ((2*n+0.25) **0.5-0.5)         return K

2018-10-03 21:33:05

leetcode--441--Arranging coins