0441. Arranging Coins

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

Description

You have n coins and you want to build a staircase with these coins. The staircase consists of k rows where the ith row has exactly i coins. The last row of the staircase may be incomplete.

Given the integer n, return the number of complete rows of the staircase you will build.

Example 1:

**Input:** n = 5
**Output:** 2
**Explanation:** Because the 3rd row is incomplete, we return 2.

Example 2:

**Input:** n = 8
**Output:** 3
**Explanation:** Because the 4th row is incomplete, we return 3.

Constraints:

• 1 <= n <= 231 - 1

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