Problem:
Score : 300 points

Problem Statement

Takahashi is standing on a multiplication table with infinitely many rows and columns.

The square (i,j) contains the integer i \times j. Initially, Takahashi is standing at (1,1).

In one move, he can move from (i,j) to either (i+1,j) or (i,j+1).

Given an integer N, find the minimum number of moves needed to reach a square that contains N.

Constraints

2 \leq N \leq 10^{12}

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

Print the minimum number of moves needed to reach a square that contains the integer N.

Sample Input 1

10

Sample Output 1

5

(2,5) can be reached in five moves. We cannot reach a square that contains 10 in less than five moves.

Sample Input 2

50

Sample Output 2

13

(5, 10) can be reached in 13 moves.

Sample Input 3

10000000019

Sample Output 3

10000000018

Both input and output may be enormous.

Solution in C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Contest20191029
{
    class Program
    {
        static void Main(string[] args)
        {
            double n = double.Parse(Console.ReadLine());
            List <double> ans= new List<double>();
            double k = n;

            for(int i = 1; i < k; i++)
            {

                if(n % i == 0)
                {
                    ans.Add(k - 1 + i - 1);
                   
                }
                k = n / (i + 1);
                k = Math.Ceiling(k);

            }
            ans.Sort();

            Console.WriteLine(ans[0]);


        }
    }
}