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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include<iostream>
#include <stdlib.h>
#include<ctime>
#include <string>
#include<string.h>
#include<algorithm>
#include<vector>
#include<math.h>
using namespace std;

int main()
{
	int a;
	scanf("%d", &a);
	int minm = a;
	for (int i = 1; i < sqrt(a); i++)
	{
		for (int j = 1; j <a; j++)
		{
			if (i*j == a)
			{
				minm = min(minm, i + j - 2);
			}
		}
	}
	printf("%d", minm);
	return 0;
}