You have a cubic storeroom where the width, length, and height of the room are all equal to `n`

units. You are asked to place `n`

boxes in this room where each box is a cube of unit side length. There are however some rules to placing the boxes:

- You can place the boxes anywhere on the floor.
- If box
`x`

is placed on top of the box`y`

, then each side of the four vertical sides of the box`y`

**must**either be adjacent to another box or to a wall.

Given an integer `n`

, return* the minimum possible number of boxes touching the floor.*

**Example 1:**

Input:n = 3Output:3Explanation:The figure above is for the placement of the three boxes. These boxes are placed in the corner of the room, where the corner is on the left side.

**Example 2:**

Input:n = 4Output:3Explanation:The figure above is for the placement of the four boxes. These boxes are placed in the corner of the room, where the corner is on the left side.

**Example 3:**

Input:n = 10Output:6Explanation:The figure above is for the placement of the ten boxes. These boxes are placed in the corner of the room, where the corner is on the back side.

**Constraints:**

`1 <= n <= 10`

^{9}

class Solution {
public int minimumBoxes(int n) {
}
}