Factorial in D Language -

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i have started d , trying write simple factorial program in d. there vectors of c++ in d? wanted use vectors create dynamic function compute factorial.

why don't use std.bigint? - it's optimized arbitrary-precision numerics. ulong (2^64) can compute factorial until 20 , use-case inline-table might make more sense. here's example bigint:

import std.bigint : bigint;  bigint factorial(int n) {     auto b = bigint(1);     foreach (i; 1..n + 1)         b *= i;     return b; }  void main () {     import std.stdio : writeln;     factorial(10).writeln; // 3628800     factorial(100).writeln; // 9.33 * 10^157 }

if want learn more dynamic arrays, maybe dlang tour pages arrays or slices might you?


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