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Hi....can anyone help me to explain what is the use of isPrime=true;

in the last line of this coding..??

I found that it is very important because if i delete it, the answer of the prime number will always constantly 2 and 3..

Even if i put 7 as the input ,the result will also became 2 and 3. The 4 and 7 is not there..Can anyone explain this ??

Then,,i also want to find the total element of the prime number...

For Example The output will became like this..

Enter a number and I will generate the prime numbers up to that number: 7

Prime : 2

Prime : 3

Prime : 5

Prime : 7

The total is :4

How is it?..

Please anyone..help me to get out from this frustrating..

Thanks so much..

```
#include <iostream>
void primeNum(int num);
using namespace std;
int main()
{
int n;
cout << " Enter a number and I will generate the prime numbers up to that number: ";
cin >> n;
primeNum(n);
}
void primeNum(int num)
{
bool isPrime=true;
for (int i = 2; i <= num; i++)
{
for ( int j = 2; j <i; j++)
{
if ( i % j == 0 )
{
isPrime=false;
break;
}
}
if (isPrime)
{
cout <<"Prime:"<< i << endl;
}
isPrime=true; //WHAT it is mean??
}
```

*Edited 6 Years Ago by ireimaima*: to edit something