关于精馏塔理论塔板数的计算

这个到底是什么问题........

我这里倒是有HUFFMAN法的文件压缩过程:
#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#include<string.h>
#include<math.h>

struct htnode
{
char ch;
int weight,parent,lchild,rchild;
};
struct hc
{
char *code;
char word;
int size;
};

void select(struct htnode * ht,int n,int& s1, int& s2)
{
int small1=9999, small2=9999,i;
for(i=1;i<=n-1;i++)
{
if(ht[i].weight<small1&&ht[i].parent==0)
{
small1=ht[i].weight;
s1=i;
}
++i;
if(ht[i].weight<small2&&ht[i].parent==0)
{
small2=ht[i].weight;
s2=i;
}
}
}

void reduce()
{
FILE *fpin,*fpout;
int cut[32768];
int i,k;
char flag;
double j=0;
for(i=0;i<=32768;i++)
cut[i]=0;
fpin=fopen("code.txt","r&qu