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20180927
BigInteger

ref:
https://docs.microsoft.com/en-us/dotnet/api/system.numerics.biginteger?redirectedfrom=MSDN&view=netframework-4.7.2

BigInter Note:
  1. Must add reference to System.Numeric.
  2. The BigInteger type is an immutable type that represents an arbitrarily large integer whose value in theory has no upper or lower bounds.
  3. 由於是 immutable type, 效能較差, 不適用於大量運算.


The BigInteger type is an immutable type that represents an arbitrarily large integer whose value in theory has no upper or lower bounds. The members of the BigInteger type closely parallel those of other integral types (the Byte, Int16, Int32, Int64, SByte, UInt16, UInt32, and UInt64 types). This type differs from the other integral types in the .NET Framework, which have a range indicated by their MinValue and MaxValue properties. 

Because the BigInteger type is immutable (see Mutability and the BigInteger Structure) and because it has no upper or lower bounds, an OutOfMemoryException can be thrown for any operation that causes a BigInteger value to grow too large.