Weird exponentiation error

Question

So, I have this code, which works fine for the first 4 numbers, but then it gives a wrong number, What's the problem? (I know I can also use Math.pow, but I wanted to try doing it myself first)

public static void main(String [] args){

    int number = 98;        
    int result = number;        
    int exponentt = 5;
    int exponent = exponentt--;     
    System.out.println(Math.pow(number, exponent));
    for (int i = 0; i < exponentt ;i++) {
        result = result * number;
        System.out.println(result );            
    }
}

Console: 9604 92236816 449273376

int32 only can store up to 2,147,483,647 – DarkBee Jul 29 '14 at 14:14 — DarkBee, Jul 29 '14 at 14:14

score 0 · Accepted Answer · answered Jul 29 '14 at 14:14

Switch your int number to a long and you will get the right result.

public static void main(String [] args){

    **long** number = 98;        
    **long** result = number;        
    int exponentt = 5;
    int exponent = exponentt--;     
    System.out.println(Math.pow(number, exponent));
    for (int i = 0; i < exponentt ;i++) {
        result = result * number;
        System.out.println(result );            
    }
}

It's going outside of the range for the int and giving you weird results. int can only store up to 2,147,483,647 -- 98^4 is well over that (9,039,207,968)

And in general use java.math.BigInteger because at that rate long can end up very quickly — abc, Jul 29 '14 at 14:33

Weird exponentiation error

1 Answers1