biginteger

问题 I need to add two very big integers 46376937677490009712648124896970078050417018260538 + 37107287533902102798797998220837590246510135740250; What's wrong with this? BigInteger f = 37107287533902102798797998220837590246510135740250; How I can solve this problem in Java using BigInteger ? 回答1: The problem here is that 3710... will be interpreted as an int , and so it will be out of range. Essentially what you're trying to do is to create an int , and then convert it to a BigInteger , and the

问题 When gcc sees multiplication or division of integer types that isn't supported in hardware, it generates call to special library function. http://gcc.gnu.org/onlinedocs/gccint/Integer-library-routines.html#Integer-library-routines According link above, long __divdi3 (long a, long b) used for division of long. However, here http://gcc.gnu.org/onlinedocs/gcc-3.3/gccint/Library-Calls.html divdi explained as "call for division of one signed double-word". When first source has cleary mapping of di

问题 So I'm working on a program in C# using ideone and I'm working with Mono for the first time. I'm trying to use the BigInteger class (Mono.Math.BigInteger) but I keep getting errors. Here's me code below. What is going on and how do I fix it? Thanks. using System; using Mono.Math; public class TFIB { public static int Main() { const int FIB_SEQUENCE_SIZE = 300; BigInteger[] FibonacciSequence = new BigInteger[FIB_SEQUENCE_SIZE]; // Calculate Fibonacci Sequence FibonacciSequence[0] = 0;

问题 So consider the following program-segment! I've tried to use the basic recursion function to determine the factorial of a number, but now using the BigInteger class. public static BigInteger fact(int a) { BigInteger factorial = BigInteger.ONE; BigInteger factz = BigInteger.ONE; if(a == 1) { return factorial; } else { return factz.multiply(fact(a-1)); } } So when I try implementing this in a program, it returns the output as 1. Is it because BigInteger objects are immutable? Or am I missing

问题 This question already has answers here : How to generate a random BigInteger value in Java? (7 answers) Closed 5 years ago . I need to get a random BigInteger that is bigger than 2^511 and lower than 2^512. 回答1: byte[] bytes = new byte[64]; // 512 bits new Random().nextBytes(bytes); bytes[0] |= 0x80; // set the most significant bit return new BigInteger(1, bytes); 回答2: This solution creates at first a BigInteger with value 2^511 and afterwards adds an value between 0 and 2^511 - 1:

问题 I want to calculate the slope of a line. public sealed class Point { public System.Numerics.BigInteger x = 0; public System.Numerics.BigInteger y = 0; public double CalculateSlope (Point point) { return ((point.Y - this.Y) / (point.X - this.X)); } } I know that BigInteger has a DivRem function that returns the division result plus the remainder but am not sure how to apply it to get a double. The numbers I'm dealing with are far far beyond the range of Int64.MaxValue so the remainder itself

问题 In Java, to convert a String to BigInteger you use the constructor new BigInteger(String) but to convert an int/long you use the factory function BigInteger.valueof(long) , why is that? 回答1: There actually is a BigInteger(long) constructor, but it's private. The javadoc on the factory method provides info on why: This "static factory method" is provided in preference to a (long) constructor because it allows for reuse of frequently used BigIntegers. 回答2: @Morad you can find the answer in the

问题 I'm wondering about the performance/ complexity of constructing BigInteger objects with the new BigInteger(String) constructor. Consider the following method: public static void testBigIntegerConstruction() { for (int exp = 1; exp < 10; exp++) { StringBuffer bigNumber = new StringBuffer((int) Math.pow(10.0, exp)); for (int i = 0; i < Math.pow(10.0, exp - 1); i++) { bigNumber.append("1234567890"); } String val = bigNumber.toString(); long time = System.currentTimeMillis(); BigInteger bigOne =

问题 How do I compare an int with a BigInteger in Java? I specifically need the know if an int is less than a BigInteger . Here is the code I am using: private static BigInteger two = new BigInteger("2"); private static BigInteger three = new BigInteger("3"); private static BigInteger zero = new BigInteger("0"); public static BigInteger bigIntSqRootCeil(BigInteger x) throws IllegalArgumentException { if (x.compareTo(BigInteger.ZERO) < 0) { throw new IllegalArgumentException("Negative argument.");

问题 Is there a method in BigInteger to get the 2's complement value? For eg: if there is a BigInteger with a negative value BigInteger a = new BigInteger("-173B8EC504479C3E95DEB0460411962F9EF2ECE0D3AACD749BE39E1006FC87B8", 16); then I want to get the 2's complement in a BigInteger form BigInteger b = E8C4713AFBB863C16A214FB9FBEE69D0610D131F2C55328B641D61EFF9037848 I can subtract the first BigInteger from 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF to get the second