/*  slflfact.cpp  by K.Tsuru  */
// function ID = 2001   DRADIX(reference)
/****************************************************************************
SLong class
It provides the factrial n! using the SLong arithmetic. It is very slow in
comparison with FactPF() in which the prime factorization is used.
****************************************************************************/
#ifndef SN_H
#include "sn.h"
#endif
SLong LFact(ulong n){
    //the number of figure by Stirling's formula in the decimal system
    long sn  = Stirling(n);
    long fig = sn/DFIGURES; //in the radix DRADIX
    if(sn % DFIGURES) fig++;

    SLong  result(SNumber::DEC_INT, (uint)fig, 1.0);    // result = 1
    ulong j;

    for(j = 2uL; j <= n; j++) result = LsMult(result, j);

    return result;
}