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 (Clang 3.8.0) (judge verdict: Wrong Answer)

#include<stdio.h>

int main (){
	long int N,min,moves;
	scanf("%ld",&N);
	long int i,j,c;
	min = 0;
	moves = 0;
	c = 1;
	for (i=1;i<N;i++){
		for (j=1;j<N;j++){
			if (i*j==N){
				if (c==1){
				moves=(i-1)+(j-1);
				min=moves;
			     c++;
			     }
				else{
				    moves=(i-1)+(j-1);
				    if (moves<min)
				    min=moves;
			     }
			}
		}
	}
	printf("%ld\n",min);
	return 0;
}