44 lines
1.5 KiB
Markdown
Vendored
44 lines
1.5 KiB
Markdown
Vendored
# mruby-bigint
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mruby-bigint is an mrbgem that provides multi-precision integer (BigInt) support for mruby. It allows you to work with integers that are larger than the standard Integer type can handle.
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This extension uses fgmp, which is a public domain implementation of a subset of the GNU gmp library by Mark Henderson <markh@wimsey.bc.ca>.
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But it's heavily modified to fit with mruby. You can get the original source code from <https://github.com/deischi/fgmp.git>.
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You can read the original README for fgmp in [README-fgmp.md](README-fgmp.md).
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If you want to create your own Multi-precision Integer GEM, see [examples/mrbgems/mruby-YOUR-bigint/TODO-HINT.md](../../examples/mrbgems/mruby-YOUR-bigint/TODO-HINT.md).
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## Features
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- Basic arithmetic operations: `+`, `-`, `*`, `/`, `%`
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- Power operation: `**`
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- Modular exponentiation
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- Bitwise operations: `&`, `|`, `^`, `<<`, `>>`
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- Comparison: `<=>`
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- Conversion to and from strings: `to_s`, `String#to_i` (with base)
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- Square root
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- Greatest Common Divisor (GCD) (available if `MRB_USE_RATIONAL` is defined)
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## Usage
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Here are some simple examples of how to use mruby-bigint:
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```ruby
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# Creating BigInts
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a = BigInt(12345678901234567890)
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b = "98765432109876543210".to_i(10) # Specify base 10 for string conversion
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# Arithmetic operations
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c = a + b
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puts c.to_s # Output: 111111111011111111100
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d = a * 2
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puts d.to_s # Output: 24691357802469135780
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# Comparison
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puts a <=> b # Output: -1
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```
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## fgmp Dependency
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mruby-bigint depends on fgmp. For more information about fgmp, please see [README-fgmp.md](README-fgmp.md).
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