Problem:
Score : 400 points

Problem Statement

Given is a positive integer N. Consider repeatedly applying the operation below on N:

First, choose a positive integer z satisfying all of the conditions below:

z can be represented as z=p^e, where p is a prime number and e is a positive integer;

z divides N;

z is different from all integers chosen in previous operations.

Then, replace N with N/z.

Find the maximum number of times the operation can be applied.

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 maximum number of times the operation can be applied.

Sample Input 1

24

Sample Output 1

3

We can apply the operation three times by, for example, making the following choices:

Choose z=2 (=2^1). (Now we have N=12.)

Choose z=3 (=3^1). (Now we have N=4.)

Choose z=4 (=2^2). (Now we have N=1.)

Sample Input 2

1

Sample Output 2

0

We cannot apply the operation at all.

Sample Input 3

64

Sample Output 3

3

We can apply the operation three times by, for example, making the following choices:

Choose z=2 (=2^1). (Now we have N=32.)

Choose z=4 (=2^2). (Now we have N=8.)

Choose z=8 (=2^3). (Now we have N=1.)

Sample Input 4

1000000007

Sample Output 4

1

We can apply the operation once by, for example, making the following choice:

z=1000000007 (=1000000007^1). (Now we have N=1.)

Sample Input 5

997764507000

Sample Output 5

7

Solution in PyPy3 (7.3.0) (judge verdict: Wrong Answer)

import sys
import math


def is_prime(N):
    if N == 1:
        return False
    i = 2
    while i * i <= N:
        if N % i == 0:
            return False
        i += 1
    return True

def prime(N):
    prime = []
    is_prime = [True for i in range(N+1)]  # 全て素数であると初期化
    is_prime[0] = is_prime[1] = False # 0,1は素数ではない
    for i in range(2, N+1):
        if is_prime[i]:
            # iは素数である
            prime.append(i)
            for j in range(2 * i, N+1, i):
                # iの倍数は素数でない
                is_prime[j] = False
    # N以下の素数を表示
    return prime

def main():
    N = int(input())
    if N == 1:
        print(0)
        sys.exit()
    if is_prime(N):
        print(1)
        sys.exit()
    else:
        n = math.ceil(math.sqrt(N))
        prime_list = prime(n)
        ans = []
        for i in range(len(prime_list)):
            now = prime_list[i]
            j = 1
            while now ** j <= N:
                ans.append(now ** j)
                j += 1
        ans.sort()
        count = 0
        for i in range(len(ans)):
            now = ans[i]
            if N < now:
                break
            if N % now == 0:
                count += 1
                N //= now
        print(count)

if __name__ == '__main__':
    main()