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 (GCC 5.4.1) (judge verdict: Runtime Error)

#include<stdio.h>
int main(void)
{
	long n,a[100000000000000],p=0,x,y,i=1;
	scanf("%ld", &n);
	while(i*i<=n)
	{
		if(n%i==0)
		{
			a[p]=i;
			p++;
		}
		i++;
	}
	x=p;
	for(i=p-1; i>=0; i--)
	{
		a[x]=n/a[i];
		x++;
	}
	if(a[p-1]==1)
	x=1;
	else
	x=2;
	printf("%ld\n", a[p]+a[p-1]-x);
	
	return 0;
}