arranging-coins.js

// 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.

/**
 * @param {number} n
 * @return {number}
 */
var arrangeCoins = function(n) {
    if(n==1 || n==0) return n
    let i = 1,count = 0
    while(n-i >= 0){
        n = n - i
        count++
        i++
    }
    return count
};