### Dont understand

Write a program that prompts the user to enter an integer and then displays that integer as a product of its primes and if it is a prime then it should say so??

Above is the question I have been given

#include <iostream>
#include <vector>

using namespace std;

int main ()
{
int num, result;
cout << "Enter A Number " << endl;

system ("pause");
return 0;
}

This is what I have so far, do I have to use a for loop, a while loop or a do loop,

and if it is possible can someone give me an example of how to it.
thanks very much appreciated
Need to use vecotrs in the code
Use this to check for for prime numbers.

http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes.

Basically, this exercise is preparing you for a particular cryptography concept, such as RSA
Last edited on
 Need to use vecotrs in the code

Nah, mate its cool
Guys,
I have changed the code around to this,
#include <iostream>
using namespace std;

int main() {

// Declaring Variables

int perfect;
int counter;
int num1;

//initialize variables

cout<<"This program will tell you the prime factorization of a number"<<endl;
cout<<"Please input a number and press [ENTER]."<<endl;
cin>>num1;

for (counter=1;counter<=num1;counter++)
{
if (num1%counter==0)

cout<<"The possible factors of that number are "<< counter <<endl;
}

return 0;

}

and it is showing me all the possible factors of the number that I enter, I only want it to show the Prime numbers
I have now changed my code to this,
#include <iostream>

using namespace std;

int main()
{
int n, c = 2;

printf("Enter a number to check if it is prime\n");
scanf("%d",&n);

for ( c = 2 ; c <= n - 1 ; c++ )
{
if ( n%c == 0 )
{
printf("%d is not prime.\n", n);
break;
}
}
if ( c == n )
printf("%d is prime.\n", n);
system ("pause");
return 0;
}
can anyone explain to me on how i can get the prime numbers shown of the number that is entered
Last edited on
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