lispval
Lminus()
{
register lispval arg1, handy;
lispval subbig();
chkarg(1,"minus");
arg1 = lbot->val;
handy = nil;
switch(TYPE(arg1)) {
case INT:
handy= inewint(0 - arg1->i);
break;
case DOUB:
handy = newdoub();
handy->r = -arg1->r;
break;
case SDOT: { struct sdot dummyb;
handy = (lispval) &dummyb;
handy->s.I = 0;
handy->s.CDR = (lispval) 0;
handy = subbig(handy,arg1);
break; }
default:
error("non-numeric argument",FALSE);
}
return(handy);
}
void egcdbig(int *a,int *b,int *d,int *x,int *xf,int *y,int *yf)
{
static BG z[2000];
static BG t;
int f,now;
now=++C;
if(iszero(b)){cpybig(d,a);x[0]=x[1]=y[0]=1;y[1]=0;*xf=*yf=0;return;}
divmodbig(a,b,z[now]);
egcdbig(b,a,d,x,xf,y,yf);
mulbig(z[now],y,t);
cpybig(z[now],y);
f=*yf;
if(*xf==0 && *yf==0)
{
if(cmpbig(x,t)>=0)
subbig(x,t,y);
else
{
subbig(t,x,y);
*yf=1;
}
}
else if(*xf==0 && *yf==1)
{
addbig(x,t,y);
*yf=0;
}
else if(*xf==1 && *yf==0)
{
addbig(x,t,y);
*yf=1;
}
else if(*xf==1 && *yf==1)
{
if(cmpbig(x,t)>0)
subbig(x,t,y);
else
{
subbig(t,x,y);
*yf=0;
}
}
cpybig(x,z[now]);
*xf=f;
}