CF859B.Lazy Security Guard

Your security guard friend recently got a new job at a new security company. The company requires him to patrol an area of the city encompassing exactly N city blocks, but they let him choose which blocks. That is, your friend must walk the perimeter of a region whose area is exactly N blocks. Your friend is quite lazy and would like your help to find the shortest possible route that meets the requirements. The city is laid out in a square grid pattern, and is large enough that for the sake of the problem it can be considered infinite.

你的保安朋友最近在一家新的安保公司找到了一份新工作。该公司要求他巡逻城市中恰好包含 N 个街区的区域，但允许他自己选择具体是哪些街区。也就是说，你的朋友必须沿一个面积恰好为 N 个街区的区域的周界行走。你的朋友非常懒惰，希望你能帮他找出满足要求的最短可能路线。城市呈正方形网格布局，且范围足够大，因此在本题中可将其视为无限大。

Input will consist of a single integer N (1 ≤ N ≤ 106), the number of city blocks that must be enclosed by the route.

输入将包含一个整数 $N$（$1 \leq N \leq 10^6$），表示路线必须围住的城市街区数量。

Print the minimum perimeter that can be achieved.

输出所能达到的最小周长。

Here are some possible shapes for the examples:

以下是一些示例可能的形状：