/*  srmredc.cpp  by K.Tsuru  */
// function ID = 801  BRADIX
/*****************************
SRational class
It provides a reducuction.
*****************************/
#ifndef SN_H
#include "sn.h"
#endif

static const uint initReduceSize = 512u;    //initial value of reduceSize
uint SRational::reduceSize = initReduceSize;

void SRational::reduce(bool must){
    if( !num.Sign(801) ){  SetZero();  return; }        //numerator is zero
    if( num.IsOne() || den.IsOne() ) reduceDone = true; //numerator or denominator is one
    if( reduceDone == true ) return;

// reduceDone = false
//When the number of figures is small it does not reduce.
    if( !must && ( max( num.Head(), den.Head() ) < reduceSize) ) return;
//To make the reduction as late as possible it divides num and den by 2^b*R^r.
    if( !(num[0] % 2u) && !(den[0] % 2u) )  ReduceByPow2Rdx(num, den);
    if( !must && ( max( num.Head(), den.Head() ) < reduceSize) ) return;
//reduction
    SLong d = gcdL(num, den);   // d > 0, type of d is BIN_INT
    num /= d;    den /= d;
    reduceDone = true;
//When the calculation for large figures continues it enlarges the value of reduceSize.
    uint rds = min(num.Head(), den.Head()) +1u;
    if(rds > reduceSize) reduceSize = min(4u*rds, num.MaxSize());
    else reduceSize = initReduceSize;
}