Given N dots that form a triangle such that i^{th }line contains i number of dots.
.
. .
. . .
. . . .
Find the minimum hieght H of the triangle that can be formed using these N dots.

Example 1:
Input: N = 2
Output: 1
Explaination: The height will be 1. We
need one dot to create first line. With
the remaining one dot we cannot complete the
second line.

Example 2:
Input: N = 10
Output: 4
Explaination: With 10 dots we can complete
total four lines. The layers will have 1,
2, 3 and 4 dots respectively.

Your Task:
You do not need to read input or print anything. Your task is to complete the function height() which takes N as input parameter and returns the height of the triangle that we can form using N dots.

Expected Time Comlpexity: O(1)
Expected Auxiliary Space: O(1)

Constraints:
1 ≤ N ≤ 10^{5}

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