Help with finding only prime numbers with for loops

So I'm new at all of this programming jazz and I could really use some help. The assignment has already been turned in, I would just like to figure this out before we move in class. Teacher isn't in town so I can't ask him for the moment. Could really use your help. Thanks. :)

So this is the assignment...

A prime number is a number greater than 1 which is only evenly divisible by 1 and itself. For this assignment you will find which numbers from 2 to *n* (where *n* is a user-specified number) are prime.

Ask the user for a number, *n*, greater than 2. Keep asking for a number until a number greater than 2 is provided. Assume that the user will only enter numbers (that is, you do not need to check if a user enters text).

Use a loop to iterate on a variable, i, from 2 through n. For each iteration, check all numbers from 2 through* i* to determine whether the number is prime. If it is prime, print out *i* and the word "Prime".

Use the modulus operator, **%**, to determine if a number is prime

Example output:

**Please enter a number larger than two:** **-939**

**Please enter a number larger than two:** **2**

**Please enter a number larger than two:** **20**

**2 Prime**

**3 Prime**

**5 Prime**

**7 Prime**

**11 Prime**

**13 Prime**

**17 Prime**

**19 Prime**

This is what I have so far. I suppose i'm not really understanding how to continue with the second for loop. The first one just prints out a list of numbers from 2 to the number designated by the user. In my case that variable is user_input.

Code:

`// Alen`

// Prime

//

# include <iostream>

using namespace std;

int main()

{

int user_input;

int i;

int n = 1;

int total=2;

do {

cout << "Enter a number greater than 2." << endl;

cin >> user_input;

} while (user_input<=2);

for (i=2; i < user_input; i++)

{

** } **

return 0;

}