[441] Arranging Coins

https://leetcode.com/problems/arranging-coins/description/

• algorithms
• Easy (36.85%)
• Source Code: 441.arranging-coins.py
• Total Accepted: 66.9K
• Total Submissions: 177.3K
• Testcase Example: '5'

You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins.

Given n, find the total number of full staircase rows that can be formed.

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

Example 1:

n = 5

The coins can form the following rows: ¤ ¤ ¤ ¤ ¤

Because the 3rd row is incomplete, we return 2.

Example 2:

n = 8

The coins can form the following rows: ¤ ¤ ¤ ¤ ¤ ¤ ¤ ¤

Because the 4th row is incomplete, we return 3.

class Solution(object):
    def arrangeCoins(self, n):
        """
        :type n: int
        :rtype: int
        """
        total = 0
        i = 1
        level = 0
        while total+i <= n:
            total += i
            i += 1
            level += 1

        return level