How do I print prime numbers between any two given numbers?
for e.g.
Between 2 and 10
2,3,5,7
Likewise between any two numbers.
Thanks
Prime Numbers 
+2  Akhilesh Chobey · November 18, 2015 
Post a Reply 
Replies page 1 
Oldest Newest Rating 
+2 
Jon Z.
· November 18, 2015
This should do.

0 
Akhilesh Chobey
· November 19, 2015
Hey Jon Z. thanks for that.
I am not so good with functions though. Better watch the functions tutorial again. However if possible could you just explain in short as to what test you performed? Thanks again 
+3 
Scott Walker
· November 19, 2015
Essentially, the 2 parameters are your start and end, for example 5 and 10.
In the outer for loop, you assign i to the start digit (5) and say as long as it is less than 'end'(10) increment it by 1 (standard loop). assign k to 0. inner for loop. whilst j is less than i, increment j by 1. if statement: if i (currently 5) / j (currently 2) has a remainder of 0 then increment k by 1, loop again. if i (currently 5) / j (currently 3) has a remainder of 0 then increment k by 1, loop again if i (currently 5) / j (currently 4) has a remainder of 0 then increment k by 1, loop again. At the end of the loop, if none of the ifs were true, k will still be equal to 0 meaning it is prime, it then prints it :). 
0 
Carson Radtke
· November 20, 2015

0 
Akhilesh Chobey
· November 20, 2015
Hey @Scott
. Thanks for explaining. Just one more doubt. for 5,first k=0. 5%2 is not 0. Now k=1.Similarly 5%3 and 5%4 isn't zero. So k becomes 2 and 3. Right? How does an increment in k help us? All other explanation is crystal clear 
0 
Scott Walker
· November 20, 2015
essentially, the incrementing of 'k' doesn't matter, it just means so at the end of the for loop 'k' is either 0 or something else, it doesn't matter if k is 1 or 64756 etc as long as it isn't 0. The if statement then checks if it's 0, if it is it prints the value as it must be a prime number. is that ok??

0 
Akhilesh Chobey
· November 21, 2015
Okay. Yes!
Now I get it.Thanks a lot! 
+2 
Jon Z.
· November 26, 2015
Thanks Scott for explaining my code.
Also if you want to improve performance you can break; right after k++;. That way once k is no longer 0 you don't need to continue looping. 
0 
Scott Walker
· November 27, 2015
^^ I was going to mention that but I wasn't sure if in 'C' it would break out of both loops

0 
Deepak Panday
· November 27, 2015

 1
 2