BigInt

C++ class/lib to handle integer arbitrary length.

List Of Content

• Description

• Usage

  • Initialization & Assignment

  • Input/Output

  • Operators

    • Arithmetic Operators

      1. Addition
      2. Subtraction
      3. Multiplication
      4. Division

    • Comparison Operator

Description

I have made a c++ class that can handle both integers as well as an integer of arbitrary length.

This class can work with different operators such as +, -, * and / [Not stable yet. will be updated soon].

I have also used make to automate the build for my project.

If you want to contribute to this project you are also very welcome 😀. You can also raise issues if you find a bug or any suggestion about modification.

Usage

Note- Namespace used is bigint.

You can include namespace like this:

using namespace bigint;

or can used :: scope resolution operator to include the namespace.

Example:-

bigint::BigInt i = 1234567890;
std::cout<<i; //1234567890

Initialization & Assignment

Initialization is very simple and similar just like normal variables. In case if you cant to initialize arbitrary-sized integers you can pass it as a string or used the given macro function to initialize.

Demonstration:-

/**
 * I am not using namespace because if you are not using 
 * namespace for any reason you may find it difficult to use 
 * if you have no prior knowledge in c++. And this will be 
 * followed through out the documentation.
 **/

// Initializing integers.
bigint::BigInt i = 123;
// Using Macro function.
bigint::BigInt j = bigint::BIG_INT(456);
// Initializing from integer variable. 
int val = 123456;
bigint::BigInt k = val;
// Initializing from string.
k = "567";
// Default initialization
bigint::BigInt n; //0
n=j;		  //456
// Negative BigInt
bigint::BigInt neg = -1234;
neg = -i;

Input/Output

Input and Output are also similar to how we I/O integers.

Demonstration:-

bigint::BigInt i;
// Input from User
std::cin>>i;   //123456
// Output
std::cout<<i<<std::endl; //123456

Operators

Arithmetic operators

Addition

bigint::BigInt i = 12344;
bigint::BigInt j = 345;
bigint::BigInt k = BIG_INT(-452);
// Adding 3 BigInt
bigint::BigInt o = i + j + k;

Subtraction

bigint::BigInt i = 12344;
bigint::BigInt j = 345;
// Subtracting 2 BigInt
bigint::BigInt o = j - i;
// Negation operation
bigint::BigInt p = (-o);

Multiplication

bigint::BigInt i = 12344;
bigint::BigInt j = -345;
// Multiplying 2 BigInt
bigInt::Big k = i * j;

Division

bigint::BigInt i = 12344;
bigint::BigInt j = -345;
// Multiplying 2 BigInt
bigInt::Big k = i / j;

Comparison Operator