Hi techies,
I am new into C++. I like to write a program that generates all the primes number between 1 and 100. Below is the code I have written but brings no output.
Thanks for any help...

``````//A program that generates all of the prime numbers between 1 and 100

#include <iostream>

using namespace std;

int main()
{
int n;

for(n=1; n>=100; n++)
{
bool isPrime = true;

for(int i=2; i<n; i++)
{
if (n%i==0)
{
isPrime = false;
break;
}
}
if(isPrime)
{
cout<<n <<" is Prime";
}
}

return 0;
}``````

Your problem is that this for loop never runs. You have the greater than/less than sign mixed up.
change

``for(n=1; n>=100; n++)``

to

``for(n=1; n<=100; n++)``

## All 3 Replies

Your problem is that this for loop never runs. You have the greater than/less than sign mixed up.
change

``for(n=1; n>=100; n++)``

to

``for(n=1; n<=100; n++)``

As the first replier said, you've got the inequality signs all wrong. Change your code to this:

``````#include <iostream>

using namespace std;

int main()
{
int n;

for(n=1; n<101; n++)//or n<=100
{
bool isPrime = true;

for(int i=2; i<n; i++)
{
if (n%i==0)
{
isPrime = false;
break;
}
}
if(isPrime)
{
cout<<n <<" is Prime";
}
}

return 0;
}``````

Thank you for helping me out. It works...

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