#define NRANSI#include "nrutil.h"typedef struct {	unsigned long *icod,*ncod,*left,*right,nch,nodemax;} huffcode;void hufmak(unsigned long nfreq[], unsigned long nchin, unsigned long *ilong,	unsigned long *nlong, huffcode *hcode){	void hufapp(unsigned long index[], unsigned long nprob[], unsigned long n,		unsigned long i);	int ibit;	long node,*up;	unsigned long j,k,*index,n,nused,*nprob;	static unsigned long setbit[32]={0x1L,0x2L,0x4L,0x8L,0x10L,0x20L,		0x40L,0x80L,0x100L,0x200L,0x400L,0x800L,0x1000L,0x2000L,		0x4000L,0x8000L,0x10000L,0x20000L,0x40000L,0x80000L,0x100000L,		0x200000L,0x400000L,0x800000L,0x1000000L,0x2000000L,0x4000000L,		0x8000000L,0x10000000L,0x20000000L,0x40000000L,0x80000000L};	hcode->nch=nchin;	index=lvector(1,(long)(2*hcode->nch-1));	up=(long *)lvector(1,(long)(2*hcode->nch-1));	nprob=lvector(1,(long)(2*hcode->nch-1));	for (nused=0,j=1;j<=hcode->nch;j++) {		nprob[j]=nfreq[j];		hcode->icod[j]=hcode->ncod[j]=0;		if (nfreq[j]) index[++nused]=j;	}	for (j=nused;j>=1;j--) hufapp(index,nprob,nused,j);	k=hcode->nch;	while (nused > 1) {		node=index[1];		index[1]=index[nused--];		hufapp(index,nprob,nused,1);		nprob[++k]=nprob[index[1]]+nprob[node];		hcode->left[k]=node;		hcode->right[k]=index[1];		up[index[1]] = -k;		up[node]=index[1]=k;		hufapp(index,nprob,nused,1);	}	up[hcode->nodemax=k]=0;	for (j=1;j<=hcode->nch;j++) {		if (nprob[j]) {			for (n=0,ibit=0,node=up[j];node;node=up[node],ibit++) {				if (node < 0) {					n |= setbit[ibit];					node = -node;				}			}			hcode->icod[j]=n;			hcode->ncod[j]=ibit;		}	}	*nlong=0;	for (j=1;j<=hcode->nch;j++) {		if (hcode->ncod[j] > *nlong) {			*nlong=hcode->ncod[j];			*ilong=j-1;		}	}	free_lvector(nprob,1,(long)(2*hcode->nch-1));	free_lvector((unsigned long *)up,1,(long)(2*hcode->nch-1));	free_lvector(index,1,(long)(2*hcode->nch-1));}#undef NRANSI