Arranging Coins

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 {
    public int arrangeCoins(int n) {
        int i = 1;
        while(n >= 0){
            n = n-i;
            i++;
        }
        return i-2;
    }
}


Here it is one of easiest solution. Each time i increases and at same time subtract it from total coins. Repeat this step until n becomes less than 0.
Finally return i-2(i.e., to eliminate last i value and last i increment)

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