// C++ program to find if it is possible to 
// write a number n as product of exactly k 
// positive numbers greater than 1. 
#include <bits/stdc++.h> 
using namespace std; 
 
// Prints k factors of n if n can be written 
// as multiple of k numbers.  Else prints -1. 
void kFactors(int n, int k) 
{ 
    // A vector to store all prime factors of n 
    vector<int> P; 
 
    // Insert all 2's in vector 
    while (n%2 == 0) 
    { 
        P.push_back(2); 
        n /= 2; 
    } 
 
    // n must be odd at this point 
    // So we skip one element (i = i + 2) 
    for (int i=3; i*i<=n; i=i+2) 
    { 
        while (n%i == 0) 
        { 
            n = n/i; 
            P.push_back(i); 
        } 
    } 
 
    // This is to handle when n > 2 and 
    // n is prime 
    if (n > 2) 
        P.push_back(n); 
 
    // If size(P) < k, k factors are not possible 
    if (P.size() < k) 
    { 
        cout << "-1" << endl; 
        return; 
    } 
 
    // printing first k-1 factors 
    for (int i=0; i<k-1; i++) 
        cout << P[i] << ", "; 
 
    // calculating and printing product of rest 
    // of numbers 
    int product = 1; 
    for (int i=k-1; i<P.size(); i++) 
        product = product*P[i]; 
    cout << product << endl; 
} 
 
// Driver program to test above function 
int main() 
{ 
    int n = 54, k = 3; 
    kFactors(n, k); 
    return 0; 
} 

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