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 Kotlin (1.0.0) (judge verdict: Runtime Error)

fun main(args : Array<String>) {
    val n = readLine()?.toInt() ?: return
    var divisor:Int = 0
    if (n <= 2 || n >= 100000000000000) {
        return
    }
    if (isPrime(n)) {
        println(n - 1)
        return
    }

    var count = 0
    for(i in 2 .. 1000000){
        if(n % i == 0) {
            divisor = n / i
            count = i
            break
        }
    }
    println(divisor)
}

fun isPrime(number:Int): Boolean {
    var i = 1
    var divisor = 0
    while (i <= number) {
        if (number % i == 0) divisor++
        i++
    }
    return divisor == 2
}