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convert BigInteger to integer

Valerie H.

Joined: Dec 11, 2004
Posts: 6
Hello. I'm new to Java and I keep having problems doing conversions.

I am trying to convert a BigInteger to an integer in order to use
modPow(BigInteger exponent, BigInteger). I have enclosed my code below- any help or a recommended place to go would be appreciated.

BigInteger p;
BigInteger g;
BigInteger d;

int l = BigInteger.intValue(d);
BigInteger y = BigInteger.modPow(g l,p);

Thanks in advance.

Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 31896

Starting from the API:
public BigInteger modPow(BigInteger exponent, BigInteger m)

First thing to note is that modPow is not a static method. This means that you call it on a specific BigInteger (in this case g.) It takes two BigIntegers (in this case d and p.) You don't need to convert to an int. This is good as you raise to exponents that are larger than can fit in an int. Finally, it returns a BigInteger (which you are storing in y.)

So now you have:

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Valerie H.

Joined: Dec 11, 2004
Posts: 6

I tried what you suggested and it worked great. Thanks for your help on this- I really appreciate it.

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subject: convert BigInteger to integer