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authorJakob Kaivo <jkk@ung.org>2022-03-04 12:32:20 -0500
committerJakob Kaivo <jkk@ung.org>2022-03-04 12:32:20 -0500
commit55f277e77428d7423ae906a8e1f1324d35b07a7d (patch)
tree5c1c04703dff89c46b349025d2d3ec88ea9b3819 /new/big.c
import Miranda 2.066 from upstream
Diffstat (limited to 'new/big.c')
-rw-r--r--new/big.c643
1 files changed, 643 insertions, 0 deletions
diff --git a/new/big.c b/new/big.c
new file mode 100644
index 0000000..7a1cfe1
--- /dev/null
+++ b/new/big.c
@@ -0,0 +1,643 @@
+/* MIRANDA INTEGER PACKAGE */
+/* package for unbounded precision integers */
+
+/**************************************************************************
+ * Copyright (C) Research Software Limited 1985-90. All rights reserved. *
+ * The Miranda system is distributed as free software under the terms in *
+ * the file "COPYING" which is included in the distribution. *
+ *------------------------------------------------------------------------*/
+
+#include "data.h"
+#include "big.h"
+#include <errno.h>
+
+static double logIBASE,log10IBASE;
+word big_one;
+
+void bigsetup()
+{ logIBASE=log((double)IBASE);
+ log10IBASE=log10((double)IBASE);
+ big_one=make(INT,1,0);
+}
+
+word isnat(x)
+word x;
+{ return(tag[x]==INT&&poz(x));
+}
+
+word sto_word(i) /* store C long long as mira bigint */
+long long i;
+{ word s,x;
+ if(i<0)s=SIGNBIT,i= -i; else s=0;
+ x=make(INT,s|i&MAXDIGIT,0);
+ if(i>>=DIGITWIDTH)
+ { word *p = &rest(x);
+ *p=make(INT,i&MAXDIGIT,0),p= &rest(*p);
+ while(i>>=DIGITWIDTH)
+ *p=make(INT,i&MAXDIGIT,0),p= &rest(*p); }
+ return(x);
+} /* change to long long, DT Oct 2019 */
+
+#define maxval (1ll<<60)
+
+long long get_word(x) /* mira bigint to C long long */
+word x;
+{ long long n=digit0(x);
+ word sign=neg(x);
+ if(!(x=rest(x)))return(sign?-n:n);
+{ word w=DIGITWIDTH;
+ while(x&&w<60)n+=(long long)digit(x)<<w,w+=DIGITWIDTH,x=rest(x);
+ if(x)n=maxval; /* overflow, return large value */
+ return(sign?-n:n);
+}} /* change to long long, DT Oct 2019 */
+
+word bignegate(x)
+word x;
+{ if(bigzero(x))return(x);
+ return(make(INT,hd[x]&SIGNBIT?hd[x]&MAXDIGIT:SIGNBIT|hd[x],tl[x]));
+}
+
+word bigplus(x,y)
+word x,y;
+{ if(poz(x))
+ if(poz(y))return(big_plus(x,y,0));
+ else return(big_sub(x,y));
+ else
+ if(poz(y))return(big_sub(y,x));
+ else return(big_plus(x,y,SIGNBIT)); /* both negative */
+}
+
+word big_plus(x,y,signbit) /* ignore input signs, treat x,y as positive */
+word x,y; word signbit;
+{ word d=digit0(x)+digit0(y);
+ word carry = ((d&IBASE)!=0);
+ word r = make(INT,signbit|d&MAXDIGIT,0); /* result */
+ word *z = &rest(r); /* pointer to rest of result */
+ x = rest(x); y = rest(y);
+ while(x&&y) /* this loop has been unwrapped once, see above */
+ { d = carry+digit(x)+digit(y);
+ carry = ((d&IBASE)!=0);
+ *z = make(INT,d&MAXDIGIT,0);
+ x = rest(x); y = rest(y); z = &rest(*z); }
+ if(y)x=y; /* by convention x is the longer one */
+ while(x)
+ { d = carry+digit(x);
+ carry = ((d&IBASE)!=0);
+ *z = make(INT,d&MAXDIGIT,0);
+ x = rest(x); z = &rest(*z); }
+ if(carry)*z=make(INT,1,0);
+ return(r);
+}
+
+word bigsub(x,y)
+word x,y;
+{ if(poz(x))
+ if(poz(y))return(big_sub(x,y));
+ else return(big_plus(x,y,0)); /* poz x, negative y */
+ else
+ if(poz(y))return(big_plus(x,y,SIGNBIT)); /* negative x, poz y */
+ else return(big_sub(y,x)); /* both negative */
+}
+
+word big_sub(x,y) /* ignore input signs, treat x,y as positive */
+word x,y;
+{ word d = digit0(x)-digit0(y);
+ word borrow = (d&IBASE)!=0;
+ word r=make(INT,d&MAXDIGIT,0); /* result */
+ word *z = &rest(r);
+ word *p=NULL; /* pointer to trailing zeros, if any */
+ x = rest(x); y = rest(y);
+ while(x&&y) /* this loop has been unwrapped once, see above */
+ { d = digit(x)-digit(y)-borrow;
+ borrow = (d&IBASE)!=0;
+ d = d&MAXDIGIT;
+ *z = make(INT,d,0);
+ if(d)p=NULL; else if(!p)p=z;
+ x = rest(x); y = rest(y); z = &rest(*z); }
+ while(y) /* at most one of these two loops will be invoked */
+ { d = -digit(y)-borrow;
+ borrow = ((d&IBASE)!=0);
+ d = d&MAXDIGIT;
+ *z = make(INT,d,0);
+ if(d)p=NULL; else if(!p)p=z;
+ y = rest(y); z = &rest(*z); }
+ while(x) /* alternative loop */
+ { d = digit(x)-borrow;
+ borrow = ((d&IBASE)!=0);
+ d = d&MAXDIGIT;
+ *z = make(INT,d,0);
+ if(d)p=NULL; else if(!p)p=z;
+ x = rest(x); z = &rest(*z); }
+ if(borrow) /* result is negative - take complement and add 1 */
+ { p=NULL;
+ d = (digit(r)^MAXDIGIT) + 1;
+ borrow = ((d&IBASE)!=0); /* borrow now means `carry' (sorry) */
+ digit(r) = SIGNBIT|d; /* set sign bit of result */
+ z = &rest(r);
+ while(*z)
+ { d = (digit(*z)^MAXDIGIT)+borrow;
+ borrow = ((d&IBASE)!=0);
+ digit(*z) = d = d&MAXDIGIT;
+ if(d)p=NULL; else if(!p)p=z;
+ z = &rest(*z); }
+ }
+ if(p)*p=0; /* remove redundant (ie trailing) zeros */
+ return(r);
+}
+
+word bigcmp(x,y) /* returns +ve,0,-ve as x greater than, equal, less than y */
+word x,y;
+{ word d,r,s=neg(x);
+ if(neg(y)!=s)return(s?-1:1);
+ r=digit0(x)-digit0(y);
+ for(;;)
+ { x=rest(x); y=rest(y);
+ if(!x)if(y)return(s?1:-1);
+ else return(s?-r:r);
+ if(!y)return(s?-1:1);
+ d=digit(x)-digit(y);
+ if(d)r=d; }
+}
+
+word bigtimes(x,y) /* naive multiply - quadratic */
+word x,y;
+{ if(len(x)<len(y))
+ { word hold=x; x=y; y=hold; } /* important optimisation */
+ word r=make(INT,0,0);
+ word d = digit0(y);
+ word s=neg(y);
+ word n=0;
+ if(bigzero(x))return(r); /* short cut */
+ for(;;)
+ { if(d)r = bigplus(r,shift(n,stimes(x,d)));
+ n++;
+ y = rest(y);
+ if(!y)
+ return(s!=neg(x)?bignegate(r):r);
+ d=digit(y); }
+}
+
+
+word shift(n,x) /* multiply big x by n'th power of IBASE */
+word n,x;
+{ while(n--)x=make(INT,0,x);
+ return(x);
+} /* NB - we assume x non-zero, else unnormalised result */
+
+word stimes(x,n) /* multiply big x (>=0) by digit n (>0) */
+word x,n;
+{ unsigned d= n*digit0(x); /* ignore sign of x */
+ word carry=d>>DIGITWIDTH;
+ word r = make(INT,d&MAXDIGIT,0);
+ word *y = &rest(r);
+ while(x=rest(x))
+ d=n*digit(x)+carry,
+ *y=make(INT,d&MAXDIGIT,0),
+ y = &rest(*y),
+ carry=d>>DIGITWIDTH;
+ if(carry)*y=make(INT,carry,0);
+ return(r);
+}
+
+word b_rem; /* contains remainder from last call to longdiv or shortdiv */
+
+word bigdiv(x,y) /* may assume y~=0 */
+word x,y;
+{ word s1,s2,q;
+ /* make x,y positive and remember signs */
+ if(s1=neg(y))y=make(INT,digit0(y),rest(y));
+ if(neg(x))
+ x=make(INT,digit0(x),rest(x)),s2=!s1;
+ else s2=s1;
+ /* effect: s1 set iff y negative, s2 set iff signs mixed */
+ if(rest(y))q=longdiv(x,y);
+ else q=shortdiv(x,digit(y));
+ if(s2){ if(!bigzero(b_rem))
+ { x=q;
+ while((digit(x)+=1)==IBASE) /* add 1 to q in situ */
+ { digit(x)=0;
+ if(!rest(x)){ rest(x)=make(INT,1,0); break; }
+ else x=rest(x);
+ }
+ }
+ if(!bigzero(q))digit(q)=SIGNBIT|digit(q);
+ }
+ return(q);
+}
+
+word bigmod(x,y) /* may assume y~=0 */
+word x,y;
+{ word s1,s2;
+ /* make x,y positive and remember signs */
+ if(s1=neg(y))y=make(INT,digit0(y),rest(y));
+ if(neg(x))
+ x=make(INT,digit0(x),rest(x)),s2=!s1;
+ else s2=s1;
+ /* effect: s1 set iff y negative, s2 set iff signs mixed */
+ if(rest(y))longdiv(x,y);
+ else shortdiv(x,digit(y));
+ if(s2){ if(!bigzero(b_rem))
+ b_rem = bigsub(y,b_rem);
+ }
+ return(s1?bignegate(b_rem):b_rem);
+}
+
+/* NB - above have entier based handling of signed cases (as Miranda) in
+ which remainder has sign of divisor. To get this:- if signs of
+ divi(sor/dend) mixed negate quotient and if remainder non-zero take
+ complement and add one to magnitude of quotient */
+
+/* for alternative, truncate based handling of signed cases (usual in C):-
+ magnitudes invariant under change of sign, remainder has sign of
+ dividend, quotient negative if signs of divi(sor/dend) mixed */
+
+word shortdiv(x,n) /* divide big x by single digit n returning big quotient
+ and setting external b_rem as side effect */
+ /* may assume - x>=0,n>0 */
+word x,n;
+{ word d=digit(x),s_rem,q=0;
+ while(x=rest(x)) /* reverse rest(x) into q */
+ q=make(INT,d,q),d=digit(x); /* leaving most sig. digit in d */
+ { word tmp;
+ x=q; s_rem=d%n; d=d/n;
+ if(d||!q)q=make(INT,d,0); /* put back first digit (if not leading 0) */
+ else q=0;
+ while(x) /* in situ division of q by n AND destructive reversal */
+ d=s_rem*IBASE+digit(x),digit(x)=d/n,s_rem=d%n,
+ tmp=x,x=rest(x),rest(tmp)=q,q=tmp;
+ }
+ b_rem=make(INT,s_rem,0);
+ return(q);
+}
+
+word longdiv(x,y) /* divide big x by big y returning quotient, leaving
+ remainder in extern variable b_rem */
+ /* may assume - x>=0,y>0 */
+word x,y;
+{ word n,q,ly,y1,scale;
+ if(bigcmp(x,y)<0){ b_rem=x; return(make(INT,0,0)); }
+ y1=msd(y);
+ if((scale=IBASE/(y1+1))>1) /* rescale if necessary */
+ x=stimes(x,scale),y=stimes(y,scale),y1=msd(y);
+ n=q=0;ly=len(y);
+ while(bigcmp(x,y=make(INT,0,y))>=0)n++;
+ y=rest(y); /* want largest y not exceeding x */
+ ly += n;
+ for(;;)
+ { word d,lx=len(x);
+ if(lx<ly)d=0; else
+ if(lx==ly)
+ if(bigcmp(x,y)>=0)x=bigsub(x,y),d=1;
+ else d=0;
+ else{ d=ms2d(x)/y1;
+ if(d>MAXDIGIT)d=MAXDIGIT;
+ if((d -= 2)>0)x=bigsub(x,stimes(y,d));
+ else d=0;
+ if(bigcmp(x,y)>=0)
+ { x=bigsub(x,y),d++;
+ if(bigcmp(x,y)>=0)
+ x=bigsub(x,y),d++; }
+ }
+ q = make(INT,d,q);
+ if(n-- ==0)
+ { b_rem = scale==1?x:shortdiv(x,scale); return(q); }
+ ly-- ; y = rest(y); }
+} /* see Bird & Wadler p82 for explanation */
+
+word len(x) /* no of digits in big x */
+word x;
+{ word n=1;
+ while(x=rest(x))n++;
+ return(n);
+}
+
+word msd(x) /* most significant digit of big x */
+word x;
+{ while(rest(x))x=rest(x);
+ return(digit(x)); /* sign? */
+}
+
+word ms2d(x) /* most significant 2 digits of big x (len>=2) */
+word x;
+{ word d=digit(x);
+ x=rest(x);
+ while(rest(x))d=digit(x),x=rest(x);
+ return(digit(x)*IBASE+d);
+}
+
+word bigpow(x,y) /* assumes y poz */
+word x,y;
+{ word d,r=make(INT,1,0);
+ while(rest(y)) /* this loop has been unwrapped once, see below */
+ { word i=DIGITWIDTH;
+ d=digit(y);
+ while(i--)
+ { if(d&1)r=bigtimes(r,x);
+ x = bigtimes(x,x);
+ d >>= 1; }
+ y=rest(y);
+ }
+ d=digit(y);
+ if(d&1)r=bigtimes(r,x);
+ while(d>>=1)
+ { x = bigtimes(x,x);
+ if(d&1)r=bigtimes(r,x); }
+ return(r);
+}
+
+double bigtodbl(x)
+word x;
+{ word s=neg(x);
+ double b=1.0, r=(double)digit0(x);
+ x = rest(x);
+ while(x)b=b*IBASE,r=r+b*digit(x),x=rest(x);
+ if(s)return(-r);
+ return(r);
+} /* small end first */
+/* note: can return oo, -oo
+ but is used without surrounding sto_/set)dbl() only in compare() */
+
+/* not currently used
+long double bigtoldbl(x)
+word x;
+{ int s=neg(x);
+ long double b=1.0L, r=digit0(x);
+ x = rest(x);
+ while(x)b=b*IBASE,r=r+b*digit(x),x=rest(x);
+/*printf("bigtoldbl returns %Le\n",s?-r:r); /* DEBUG
+ if(s)return(-r);
+ return(r);
+} /* not compatible with std=c90, lib fns eg sqrtl broken */
+
+word dbltobig(x) /* entier */
+double x;
+{ word s= (x<0);
+ word r=make(INT,0,0);
+ word *p = &r;
+ double y= floor(x);
+/*if(fabs(y-x+1.0)<1e-9)y += 1.0; /* trick due to Peter Bartke, see note */
+ for(y=fabs(y);;)
+ { double n = fmod(y,(double)IBASE);
+ digit(*p) = (word)n;
+ y = (y-n)/(double)IBASE;
+ if(y>0.0)rest(*p)=make(INT,0,0),p=&rest(*p);
+ else break;
+ }
+ if(s)digit(r)=SIGNBIT|digit(r);
+ return(r);
+}
+/* produces junk in low order digits if x exceeds range in which integer
+ can be held without error as a double -- NO, see next comment */
+/* hugs, ghci, mira produce same integer for floor/entier hugenum, has 2^971
+ as factor so the low order bits are NOT JUNK -- 9.1.12 */
+
+/* note on suppressed fix:
+ choice of 1e9 arbitrary, chosen to prevent eg entier(100*0.29) = 28
+ but has undesirable effects, causing eg entier 1.9999999999 = 2
+ underlying problem is that computable floor on true Reals is _|_ at
+ the exact integers. There are inherent deficiences in 64 bit fp,
+ no point in trying to mask this */
+
+double biglog(x) /* logarithm of big x */
+word x;
+{ word n=0;
+ double r=digit(x);
+ if(neg(x)||bigzero(x))errno=EDOM,math_error("log");
+ while(x=rest(x))n++,r=digit(x)+r/IBASE;
+ return(log(r)+n*logIBASE);
+}
+
+double biglog10(x) /* logarithm of big x */
+word x;
+{ word n=0;
+ double r=digit(x);
+ if(neg(x)||bigzero(x))errno=EDOM,math_error("log10");
+ while(x=rest(x))n++,r=digit(x)+r/IBASE;
+ return(log10(r)+n*log10IBASE);
+}
+
+word bigscan(p) /* read a big number (in decimal) */
+ /* NB does NOT check for malformed number, assumes already done */
+char *p; /* p is a pointer to a null terminated string of digits */
+{ word s=0,r=make(INT,0,0);
+ if(*p=='-')s=1,p++; /* optional leading `-' (for NUMVAL) */
+ while(*p)
+ { word d= *p-'0',f=10;
+ p++;
+ while(*p&&f<PTEN)d=10*d+*p-'0',f=10*f,p++;
+ /* rest of loop does r=f*r+d; (in situ) */
+ d= f*digit(r)+d;
+ { word carry=d>>DIGITWIDTH;
+ word *x = &rest(r);
+ digit(r)=d&MAXDIGIT;
+ while(*x)
+ d=f*digit(*x)+carry,
+ digit(*x)=d&MAXDIGIT,
+ carry=d>>DIGITWIDTH,
+ x = &rest(*x);
+ if(carry)*x=make(INT,carry,0);
+ }}
+/*if(*p=='e')
+ { int s=bigscan(p+1);
+ r = bigtimes(r,bigpow(make(INT,10,0),s); } */
+ if(s&&!bigzero(r))digit(r)=digit(r)|SIGNBIT;
+ return(r);
+}
+/* code to handle (unsigned) exponent commented out */
+
+word bigxscan(p,q) /* read unsigned hex number in '\0'-terminated string p to q */
+ /* assumes redundant leading zeros removed */
+char *p, *q;
+{ word r; /* will hold result */
+ word *x = &r;
+ if(*p=='0'&&!p[1])return make(INT,0,0);
+ while(q>p)
+ { unsigned long long hold;
+ q = q-p<15 ? p : q-15; /* read upto 15 hex digits from small end */
+ sscanf(q,"%llx",&hold);
+ *q = '\0';
+ word count=4; /* 15 hex digits => 4 bignum digits */
+ while(count-- && !(hold==0 && q==p))
+ *x = make(INT,hold&MAXDIGIT,0),
+ hold >>= DIGITWIDTH,
+ x = &rest(*x);
+ }
+ return r;
+}
+
+word bigoscan(p,q) /* read unsigned octal number in '\0'-terminated string p to q */
+ /* assumes redundant leading zeros removed */
+char *p, *q;
+{ word r; /* will hold result */
+ word *x = &r;
+ while(q>p)
+ { unsigned word hold;
+ q = q-p<5 ? p : q-5; /* read (upto) 5 octal digits from small end */
+ sscanf(q,"%o",&hold);
+ *q = '\0';
+ *x = make(INT,hold,0),
+ x = &rest(*x);
+ }
+ return r;
+}
+
+word digitval(c)
+char c;
+{ return isdigit(c)?c-'0':
+ isupper(c)?10+c-'A':
+ 10+c-'a'; }
+
+word strtobig(z,base) /* numeral (as Miranda string) to big number */
+ /* does NOT check for malformed numeral, assumes
+ done and that z fully evaluated */
+word z; word base;
+{ word s=0,r=make(INT,0,0),PBASE=PTEN;
+ if(base==16)PBASE=PSIXTEEN; else
+ if(base==8)PBASE=PEIGHT;
+ if(z!=NIL&&hd[z]=='-')s=1,z=tl[z]; /* optional leading `-' (for NUMVAL) */
+ if(base!=10)z=tl[tl[z]]; /* remove "0x" or "0o" */
+ while(z!=NIL)
+ { word d=digitval(hd[z]),f=base;
+ z=tl[z];
+ while(z!=NIL&&f<PBASE)d=base*d+digitval(hd[z]),f=base*f,z=tl[z];
+ /* rest of loop does r=f*r+d; (in situ) */
+ d= f*digit(r)+d;
+ { word carry=d>>DIGITWIDTH;
+ word *x = &rest(r);
+ digit(r)=d&MAXDIGIT;
+ while(*x)
+ d=f*digit(*x)+carry,
+ digit(*x)=d&MAXDIGIT,
+ carry=d>>DIGITWIDTH,
+ x = &rest(*x);
+ if(carry)*x=make(INT,carry,0);
+ }}
+ if(s&&!bigzero(r))digit(r)=digit(r)|SIGNBIT;
+ return(r);
+}
+
+extern char *dicp;
+
+word bigtostr(x) /* number to decimal string (as Miranda list) */
+word x;
+{ word x1,sign,s=NIL;
+#ifdef DEBUG
+ extern word debug;
+ if(debug&04) /* print octally */
+ { word d=digit0(x);
+ sign=neg(x);
+ for(;;)
+ { word i=OCTW;
+ while(i--||d)s=cons('0'+(d&07),s),d >>= 3;
+ x=rest(x);
+ if(x)s=cons(' ',s),d=digit(x);
+ else return(sign?cons('-',s):s); }
+ }
+#endif
+ if(rest(x)==0)
+ { extern char *dicp;
+ sprintf(dicp,"%d",getsmallint(x));
+ return(str_conv(dicp)); }
+ sign=neg(x);
+ x1=make(INT,digit0(x),0); /* reverse x into x1 */
+ while(x=rest(x))x1=make(INT,digit(x),x1);
+ x=x1;
+ for(;;)
+ { /* in situ division of (reversed order) x by PTEN */
+ word d=digit(x),rem=d%PTEN;
+ d=d/PTEN; x1=rest(x);
+ if(d)digit(x)=d;
+ else x=x1; /* remove leading zero from result */
+ while(x1)
+ d=rem*IBASE+digit(x1),
+ digit(x1)=d/PTEN,
+ rem=d%PTEN,
+ x1=rest(x1);
+ /* end of in situ division (also uses x1 as temporary) */
+ if(x)
+ { word i=TENW;
+ while(i--)s=cons('0'+rem%10,s),rem=rem/10; }
+ else
+ { while(rem)s=cons('0'+rem%10,s),rem=rem/10;
+ return(sign?cons('-',s):s); }
+ }
+}
+
+word bigtostrx(x) /* integer to hexadecimal string (as Miranda list) */
+word x;
+{ word r=NIL, s=neg(x);
+ while(x)
+ { word count=4; /* 60 bits => 20 octal digits => 4 bignum digits */
+ unsigned long long factor=1;
+ unsigned long long hold=0;
+ while(count-- && x) /* calculate value of (upto) 4 bignum digits */
+ hold=hold+factor*digit0(x),
+ /* printf("::%llx\n",hold), /* DEBUG */
+ factor<<=15,
+ x=rest(x);
+ sprintf(dicp,"%.15llx",hold); /* 15 hex digits = 60 bits */
+ /* printf(":::%s\n",dicp); /* DEBUG */
+ char *q=dicp+15;
+ while(--q>=dicp)r = cons(*q,r);
+ }
+ while(digit(r)=='0'&&rest(r)!=NIL)r=rest(r); /* remove redundant leading 0's */
+ r = cons('0',cons('x',r));
+ if(s)r = cons('-',r);
+ return(r);
+}
+
+word bigtostr8(x) /* integer to octal string (as Miranda list) */
+word x;
+{ word r=NIL, s=neg(x);
+ while(x)
+ { char *q = dicp+5;
+ sprintf(dicp,"%.5o",digit0(x));
+ while(--q>=dicp)r = cons(*q,r);
+ x = rest(x); }
+ while(digit(r)=='0'&&rest(r)!=NIL)r=rest(r); /* remove redundant leading 0's */
+ r = cons('0',cons('o',r));
+ if(s)r = cons('-',r);
+ return(r);
+}
+
+#ifdef DEBUG
+wff(x) /* check for well-formation of integer */
+word x;
+{ word y=x;
+ if(tag[x]!=INT)printf("BAD TAG %d\n",tag[x]);
+ if(neg(x)&&!digit0(x)&&!rest(x))printf("NEGATIVE ZERO!\n");
+ if(digit0(x)&(~MAXDIGIT))printf("OVERSIZED DIGIT!\n");
+ while(x=rest(x))
+ if(tag[x]!=INT)printf("BAD INTERNAL TAG %d\n",tag[x]); else
+ if(digit(x)&(~MAXDIGIT))
+ printf("OVERSIZED DIGIT!\n"); else
+ if(!digit(x)&&!rest(x))
+ printf("TRAILING ZERO!\n");
+ return(y);
+}
+
+normalise(x) /* remove trailing zeros */
+word x;
+{ if(rest(x))rest(x)=norm1(rest(x));
+ return(wff(x));
+}
+
+norm1(x)
+word x;
+{ if(rest(x))rest(x)=norm1(rest(x));
+ return(!digit(x)&&!rest(x)?0:x);
+}
+
+#endif
+
+/* stall(s)
+char *s;
+{ fprintf(stderr,"big integer %s not yet implemented\n",s);
+ exit(0);
+}
+
+#define destrev(x,y,z) while(x)z=x,x=rest(x),rest(z)=y,y=z;
+/* destructively reverse x into y using z as temp */
+
+/* END OF MIRANDA INTEGER PACKAGE */
+