added quiz 2

13_while3.zig

@@ -21,6 +21,8 @@ pub fn main() void {
     // I want to print every number between 1 and 20 that is NOT
     // divisible by 3 or 5.
     while (n <= 20) : (n+=1) {
+        // The '%' symbol is the "modulo" operator and it
+        // returns the remainder after division.
         if(n % 3 == 0) ???;
         if(n % 5 == 0) ???;
         std.debug.print("{} ", .{n});