Emirp program using functions

[mnowicki]

Okay im having trouble piecing together this lab. you can view the instructions for the lab here: http://appiversity.blob.core.windows.net/instructor-1-section-18-assignment-0/3d972ae4-6a4e-4dbb-ae07-1544e6fab002_Homework3.pdf

Heres what I have so far:

#include <iostream>
using namespace std;

bool isPrime(int value); // Returns true if value is a prime number.
int reverse(int value); // Returns the reverse of the value (i.e. if value is 35, returns 53).


int main(){
	int value, count = 0;

	do{
		cout << "Please enter a positive number: ";
		cin >> value;
	} while (value < 0);

	if (isPrime(value) == 1){
		for (int test = 0; test < value; test++){
			//prime number reverse?
		}

	system("pause");
}

bool isPrime(int value){
	bool prime;
	if (value % 2 == 0 || value % 3 == 0 || value % 5 == 0 || value % 7 == 0){
		prime = false;//0
	}
	else{
		prime = true;//1
	}
	return prime;
	}

int reverse(int value){
		int rnum = 0;

		while (value) {
			rnum = rnum * 10 + (value == 10);
			value /= 10;
		}

		return rnum;
	}

any help is appreciated i need this done asapppp

[coder777]

According to your requirements the user enters the number of primes, i.e. the do while loop on line 11 is wrong.

What you basically have to do is:
- A loop that iterate as long as you haven't found enough primes
- Find a prime
- Create the counter part (e.g. 13 -> 31)
- Check whether the counter part is prime
- Loop until you reach the number of primes the user has entered

the algorithm for finding a prime is as follows:
- A loop that iterates until sqrt(value)
- If you find (value % i) != 0 -> break, no prime

[kappuccino]

If you find (value % i) != 0 -> break, no prime

value is no prime if (value % i) == 0

[Prabhat Routray]

#include <iostream>
#include<iomanip>

using namespace std;

bool isPrime(int value); // Returns true if value is a prime number.
int reverse(int value); // Returns the reverse of the value (i.e. if value is 35, returns 53).


int main()
{
int n, count = 0, i = 1, a = 1;


cout << "Please enter a positive number: ";
cin >> n;

cout<<endl<<endl;

while(count < n)
{
i++;

if(isPrime(i))
{
if(isPrime( ( reverse(i) ) ) )
{
cout<<"\t"<<i;
count++;
}
}

if( (count - (5*a)) == 0 )
{
cout<<"\n";
a++;
}
}
cout<<endl;
return 0;
}

bool isPrime( int value)
{
int test = 2, count = 0;

while(test < value)
{

if( value % test == 0)
count ++;
test++;
}
if(count == 0)
return 1;
else
return 0;
}
int reverse(int value)
{
int test = 2, rev = 0, counter;

while( value > 0)
{
rev = rev * 10 + (value % 10);
value = value / 10;
}
return rev;

}