Any body Can explain me how Prime number print I have a code and code printing prime number but didn't get the logic(javascript)

Question

Tell me please

https://code.sololearn.com/Whorxz86jinE/?ref=app

Code

Answer 1

It is a very simple approach first loop is running from 2 to 20 now for each of this value we haave to check it is prime Or not
Now we know that number is not prime if it is divisible by any number less than itself except 1
So second loop is running from 2 to that number and if any number divides that number then it is not prime so we set that to false and then outside loop we check if it's value is true then we print that number

Answer 2

Prime number is a number that has exactly 2 divisors. There is one common for all prime number, the 2 divisors are always 1 and itself.

If N is prime, there shouldn't be any divisor between 2 to N-1.

So the program loops in this range and if there is a divisor, notPrime will be true.

Side note, 1 is not prime because it only has 1 divisor, which is 1.