Problem:
Score : 500 points

Problem Statement

Snuke received a positive integer N from Takahashi.
A positive integer m is called a favorite number when the following condition is satisfied:

The quotient and remainder of N divided by m are equal, that is, \lfloor \frac{N}{m} \rfloor = N \bmod m holds.

Find all favorite numbers and print the sum of those.

Constraints

All values in input are integers.

1 \leq N \leq 10^{12}

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

8

Sample Output 1

10

There are two favorite numbers: 3 and 7. Print the sum of these, 10.

Sample Input 2

1000000000000

Sample Output 2

2499686339916

Watch out for overflow.

Solution in Kotlin (1.0.0) (judge verdict: Wrong Answer)

fun main(args : Array<String>) {
    var N = readLine()!!.toLong()
    val sqrtN = Math.sqrt(N.toDouble())
    val sqrtNInt = sqrtN.toInt()
    var count1 = 0L

    val upper = if (sqrtNInt.toDouble() == sqrtN || N.mod(2) == 0L) sqrtNInt - 1 else sqrtNInt

    (1..(upper)).forEach {a ->
        if (N.mod(a) == 0L) {
            val m = N / a - 1
            count1 += m
        }
    }
    println(count1)
}