224 lines
5.3 KiB
Markdown
224 lines
5.3 KiB
Markdown
# BigNumber
|
|
|
|
|
|
[](https://github.com/Limeoats/BigNumber/blob/master/LICENSE.md)
|
|
|
|
BigNumber is a C++ class that allows for the creation and computation of arbitrary-length
|
|
integers.
|
|
|
|
The maximum possible length of a BigNumber is `std::string::max_size`.
|
|
|
|
## Installation
|
|
To add BigNumber to your C++ project, you can download the `bin` folder from this repository, which
|
|
contains the library and include files.
|
|
|
|
Then, simply include the header file in whichever file you need a BigNumber and link to the library file.
|
|
|
|
`#include "bignumber.h"`
|
|
|
|
## Usage
|
|
### `BigNumber(string)`
|
|
|
|
|
|
You can also use the `=` operator to set a BigNumber equal to an existing BigNumber, a number, or
|
|
a string of numbers.
|
|
|
|
Examples:
|
|
|
|
BigNumber b("5"); //BigNumber b is created with value 5.
|
|
BigNumber c("-20"); //BigNumber c is created with value -20.
|
|
BigNumber d("0"); //BigNumber d is created with value 0.
|
|
BigNumber e = b; //BigNumber e is created with value 5.
|
|
BigNumber f = 30; //BigNumber f is created with value 30.
|
|
BigNumber g = "2060"; //BigNumber g is created with value 2060.
|
|
BigNumber h(22); //BigNumber h is created with value 22.
|
|
|
|
|
|
## Methods
|
|
### `add(BigNumber other)`
|
|
Adds another BigNumber to the current instance
|
|
|
|
`BigNumber("4").add(BigNumber("20")) => BigNumber("24")`
|
|
|
|
### `subtract(BigNumber other)`
|
|
Subtracts another BigNumber from the current instance
|
|
|
|
`BigNumber("30").subtract(BigNumber("45")) => BigNumber("-15")`
|
|
|
|
### `multiply(BigNumber other)`
|
|
Multiplies the BigNumber by another BigNumber
|
|
|
|
`BigNumber("12").multiply(BigNumber("4")) => BigNumber("48")`
|
|
|
|
### `divide(BigNumber other)`
|
|
Divides the BigNumber by another BigNumber
|
|
|
|
`BigNumber("30").divide(BigNumber("5")) => BigNumber("6")`
|
|
|
|
### `pow(int exponent)`
|
|
Raises the BigNumber to the power of the exponent
|
|
|
|
`BigNumber("2").pow(3) => BigNumber("8")`
|
|
|
|
### `getString()`
|
|
Returns the BigNumber as an std::string
|
|
|
|
`BigNumber("3824").getString() => "3824"`
|
|
|
|
### `setString(std::string newStr)`
|
|
Sets the BigNumber's internal number string to a new string
|
|
|
|
`BigNumber("2847").setString("38") => BigNumber("38")`
|
|
|
|
### `negate()`
|
|
Changes the sign of the BigNumber
|
|
|
|
BigNumber("3").negate() => BigNumber("-3")
|
|
BigNumber("-27").negate() => BigNumber("27")
|
|
|
|
### `equals(BigNumber other)`
|
|
Checks if the other BigNumber is equal to this one
|
|
|
|
`BigNumber("24").equals(BigNumber("28")) => false`
|
|
|
|
### `digits()`
|
|
Returns the number of digits in the BigNumber
|
|
|
|
`BigNumber("28374").digits() => 5`
|
|
|
|
### `isNegative()`
|
|
Determines whether a BigNumber is negative
|
|
|
|
`BigNumber("-278").isNegative() => true`
|
|
|
|
### `isPositive()`
|
|
Determines whether a BigNumber is positive
|
|
|
|
`BigNumber("-3").isPositive() => false`
|
|
|
|
### `isEven()`
|
|
Determines whether a BigNumber is even
|
|
|
|
`BigNumber("28472310").isEven() => true`
|
|
|
|
### `isOdd()`
|
|
Determines whether a BigNumber is odd
|
|
|
|
`BigNumber("283427").isOdd() => true`
|
|
|
|
### `abs()`
|
|
Gets the absolute value of the BigNumber
|
|
|
|
`BigNumber("-26").abs() => BigNumber("26")`
|
|
|
|
|
|
## Operator overloads
|
|
The following operators have been overloaded to work with BigNumbers:
|
|
|
|
### `<<`
|
|
Output stream operator
|
|
|
|
`std::cout << BigNumber("26") << std::endl => 26`
|
|
|
|
### `+`
|
|
Addition operator
|
|
|
|
`BigNumber("2") + BigNumber("4") => BigNumber("6")`
|
|
|
|
### `-`
|
|
Subtraction operator
|
|
|
|
`BigNumber("0") - BigNumber("2000") => BigNumber("-2000")`
|
|
|
|
### `*`
|
|
Multiplication operator
|
|
|
|
`BigNumber("-20") * BigNumber("-5") => BigNumber("100")`
|
|
|
|
### `/`
|
|
Division operator
|
|
|
|
`BigNumber("10") / BigNumber("-2") => BigNumber("-5")`
|
|
|
|
### `==`
|
|
Equal to operator
|
|
|
|
`BigNumber("24") == BigNumber("24") => true`
|
|
|
|
### `>`
|
|
Greater than operator
|
|
|
|
`BigNumber("2") > BigNumber("6") => false`
|
|
|
|
### `<`
|
|
Less than operator
|
|
|
|
`BigNumber("2") < BigNumber("6") => true`
|
|
|
|
### `>=`
|
|
Greater than or equal to operator
|
|
|
|
`BigNumber("34") >= BigNumber("22") => true`
|
|
|
|
### `<=`
|
|
Less than or equal to operator
|
|
|
|
`BigNumber("383") <= BigNumber("383") => true`
|
|
|
|
### `=`
|
|
Assignment operator
|
|
|
|
`BigNumber c("3") = BigNumber("8") => BigNumber("8")`
|
|
|
|
### `+=`
|
|
Adds and assigns to the BigNumber
|
|
|
|
`BigNumber c("4") += BigNumber("3") => BigNumber("7")`
|
|
|
|
### `-=`
|
|
Subtracts and assigns to the BigNumber
|
|
|
|
`BigNumber c("28") -= BigNumber("3") => BigNumber("25")`
|
|
|
|
### `*=`
|
|
Multiplies and assigns to the BigNumber
|
|
|
|
`BigNumber c("3") *= BigNumber("4") => BigNumber("12")`
|
|
|
|
### `/=`
|
|
Divides and assigns to the BigNumber
|
|
|
|
`BigNumber c("30") /= BigNumber("30") => BigNumer("1")`
|
|
|
|
### `++ (Prefix)`
|
|
Increments the BigNumber and returns the newly incremented number
|
|
|
|
`++BigNumber("10") => BigNumber("11")`
|
|
|
|
### `-- (Prefix)`
|
|
Decrements the BigNumber and returns the newly decremented number
|
|
|
|
`--BigNumber("34") => BigNumber("33")`
|
|
|
|
### `++ (Postfix)`
|
|
Increments the BigNumber but returns the original value
|
|
|
|
`BigNumber("20")++ => BigNumber("20")`
|
|
|
|
### `-- (Postfix)`
|
|
Decrements the BigNumber but returns the original value
|
|
|
|
`BigNumber("14")-- => BigNumber("14")`
|
|
|
|
### `[]`
|
|
Indexing operator
|
|
|
|
`BigNumber d("26")[1] => 6`
|
|
|
|
## License
|
|
This project is under the [Apache License](https://github.com/Limeoats/BigNumber/blob/master/LICENSE.md).
|
|
|
|
## Credit
|
|
The BigNumber class was created by [Mark Guerra](http://www.twitter.com/Limeoats). Visit
|
|
[Limeoats.com](http://www.limeoats.com) for more information.
|