The problem with BigDecimal, with the miltiply() method, what's the matter?

Question

Java

The problem is that I don't understand why this line return h.multiply(y); doesn't think it's right!! should return 4, but returns 8!
Here is the
package testone code;
import java.math.*;
import java.util.Scanner;
public class TestOne
{
BigDecimal s;
Big Decimal f;
Big Decimal h;
BigDecimal y;
public BigDecimal ceil (int a, int b)
{
s = BigDecimal.valueOf(a);
h = BigDecimal.valueOf(b);
y = BigDecimal.valueOf(1);
//return((a+b-1)/b);
f = ((s.add(h).subtract(y)).divide(h,BigDecimal.ROUND_HALF_DOWN));
System.out.println(" ceil ---" + f);
return f;
}
public BigDecimal getRezult(int m, int n, int a)
{
h = ceil(m , a);
System.out.println("hhhhh ---" + h);
y = BigDecimal.valueOf(0);
y = ceil(n, a);
System.out.println("yyyyyyyyyyyy ---" + y);
System.out.println("h.multiply(y) -----" + h.multiply(y));
return h.multiply(y);
//return ceil(m , a) * ceil(n , a);
}
public static void main(String[] args)
{
Scanner scan = new Scanner(System.in);
int n = scan.nextInt();
int m = scan.nextInt();
int a = scan.nextInt();
TestOne z = new TestOne();
System.out.println(z.getRezult(m, n, a));
}
}
Program output:
run:
6
6
4
ceil ---2
hhhhhh ---2
ceil ---2
yyyyyyyyyyyy ---2
h.multiply(y) -----8
8
BUILD SUCCESSFUL (total time: 10 seconds)

Answer 1

When calling y = ceil(n , a); you change the value of h

Answer 2

I beg your pardon, but when you ask your question and post the code, at least worry about its readability, because people like me may want to help, but they don’t delve into solid text.