biginteger

I am doing calculations with BigIntegers that uses a loop that calls multiply() about 100 billion times, and the new object creation from the BigInteger is making it very slow. I was hoping somebody had written or found a MutableBigInteger class. I found the MutableBigInteger in the java.math package, but it is private and when I copy the code into a new class, many errors come up, most of which I don't know how to fix. What implementations exist of a Java class like MutableBigInteger that allows modifying the value in place? Is their any particular reason you cannot use reflection to gain

public long Fib(int a1, int a2, int i){ if(i==1){ return a1; }else if(i==2){ return a2; }else{ long l1 = Fib(a1, a2, i-1); long l2 = Fib(a1, a2, i-2); long val = l2 + (l1*l1); return val; } } I wrote this code to find a Modified Fibonacci of function of t(i+2) = t(i) + t(i+1)^2 where t(i) is the answer when we find ith iterartion. But when I find t(10), it gives a separate answer. But I got correct answers till t(9). I tried BigInteger method but it gives errors. You should modify your code a little if you want to use BigInteger s. Something like: public class ModifiedFib { static BigInteger

I want to save/load a BigInteger array into/from the SharedPreferences. How can it be done? For example for the following array: private BigInteger[] dataCreatedTimes = new BigInteger[20]; Using Gson you can convert to a json String and back, which then of course makes it trivial to save in preferences: import com.google.gson.Gson; import java.math.BigInteger; public final class BigIntegerArrayJson { private BigIntegerArrayJson(){} public static String toJson(BigInteger[] array) { return new Gson().toJson(array); } public static BigInteger[] fromJson(String json) { return new Gson().fromJson

I am solving a problem such that for every given number between range (inclusive of boundary integers), I calculate the sum of the modified value of those numbers. For example, x = 388,822,442 f(388,822,442)=3800200402 i.e; makes zeros for the identical digits. f(x) is modified value. I iterated through each digit of an integer and made it zero if repeated. BufferedReader bf = new BufferedReader(newInputStreamReader(System.in)); String s[], s1[]; s = bf.readLine().trim().split("\\s+"); s1 = bf.readLine().trim().split("\\s+"); BigInteger sb = new BigInteger(s[1]); BigInteger sb1 = new

I am playing around with an idea I have for storing a public key for myself. For this I would need to transform the BigInteger in some sort of a variable and then recreate the BigInteger from that value. I have searched through Stackoverflow to find the best way to do this is with byte[]. This is my code in Eclipse: import java.math.BigInteger; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.interfaces.RSAPublicKey; public class Vaja2 { public static void main(String[] args){ try { // Create RSA Keypair (to obtain a BigInteger) KeyPairGenerator kpg =