java question

eoins23456

Just an part of an exam question for basic java having trouble with

What does the following code do?
(I think this is what the code does)The code puts the values 0,2,4 and 6 into the formula x*x+b*x+1 and outputs a value for y each time.
Give an example of the code to call the doIt method where the parameter b is 4 and the array contains the elements 0,2,4,6.
Havent a clue here
Complete the actual output produced(use a character or space per cell)
0*0+4*0+1 is 1
2*2+4*2+1 is 13
4*4+4*4+1 is 33
6*6+4*6+1 is 61


class Dowhat
public static void doIt(int b, int[] array)
for(int x: array)
int y=x*x+b*x+1
System.out.printf("y(%2d,%2d) is %3d\n",x,b,y);
//end method doIt
//end class DoWhat

Just a bit of help needed.Am i right for the first and third question and how would you do the second question? Any help appreciated!

Sparks

Ahem (with regard to the second question).

croo

Complete the actual output produced(use a character or space per cell)
0*0+4*0+1 is 1
2*2+4*2+1 is 13
4*4+4*4+1 is 33
6*6+4*6+1 is 61

You made an effort, so... do note the first y in

System.out.printf("y(%2d,%2d) is %3d\n",x,b,y);

Is in quotes! So it is a literal and the output will be in the form:
y(valueof.x, valueof.b) is valueof.y

eoins23456

y(0,4) is 1
y(2,4) is 13
y(4,4) is 33
y(6,4) is 61

I get ya now thanks
For the second questions I dont know where to start really
int[] c;
c = new int[4]
c[0]=0
c[1]=2
c[2]=4
c[3]=6

class do what
public static void doIt(int b,c) ?

dont really know where to go .

croo

re: q2 - how to call doit...
It really doesn't get any simpler than this so I could not answer without breaking the rules Sparks reminded us of. I think you need to read your java notes & book again if you have one.

But all the info you need is there in the method declaration
public static void doIt(int b, int[] array)
void will mean it does not expect a returned value
and in brackets it defiint b, int[] arraynes it expects an integer and an array of integers to be passed to it when called.