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 Python (3.8.2) (judge verdict: Accepted)

N = int(input())
divisors = []
for i in range(1, int(N**0.5)+1):
    if N % i == 0:
        divisors.append(i)
        if i != N // i:
            divisors.append(N//i)

divisors.sort()

n = len(divisors)
i = len(divisors) // 2

A, B = 0, 0
if n % 2 == 0:
    A, B = divisors[i - 1], divisors[i]
else:
    A, B = divisors[i], divisors[i]

print(A - 1 + B - 1)