Printing options

Question

Printing options
You have a document that consists of n pages and you must to print it as two pages in a paper.
If n is odd number, you must add an empty page to end of the document. And now n is even

1-step: Printing odd pages
1,3,5,...,n-1

2-step. Printing even numbers from backward
n,n-2,...,6,4,2

must find code for printing array of pages
how to code on web?

Answer 1

I think modulus should help you in this case. Since you didn't specify which language, here's an example in Java

public class Main {
public static void main(String[] argv) {
int x = 5;
if (x % 2 == 0) {
System.out.println("even");
}
if (x % 2 != 0) {
System.out.println("odd");
}
// ... or binary AND operator...
if ((x & 1) == 0) {
System.out.println("even");
}
if ((x & 1) != 0) {
System.out.println("odd");
}

}
}

Stolen from: http://www.java2s.com/Code/Java/Language-Basics/Detectevenoddnumberwiththemodulusoperator.htm