swust oj 986
哈夫曼译码
通常要求根据给定的编码本对密文进行解码。现已给定相应字符的哈夫曼编码，要求根据编码对密文进行解码。（建立哈夫曼树以及编码、主函数等都已经给出，你只需要填写译码函数void ccode(haffnode hafftree[],int n)即可。
const int maxvalue=100;
const int maxbit=100;
const int maxn=100;
#include "iostream"
#include "stdio.h"
#include "stdlib.h"
using namespace std;
struct haffnode
{
char ch;
int weight;
int flag;
int parent;
int leftchild;
int rightchild;
};
struct code
{
int bit[maxn];
int start;
int weight;
char ch;
};
void haffman(int weight[],char text[],int n,haffnode hafftree[])
{
int j,m1,m2,x1,x2,i;
for(i=0;i< 2*n-1;i++)
{
if(i < n)
{
hafftree[i].weight=weight[i];
hafftree[i].
ch=text[i];
}
else
{
hafftree[i].weight=0;
hafftree[i].ch='#';
}
hafftree[i].parent=0;
hafftree[i].flag=0;
hafftree[i].leftchild=-1;
hafftree[i].rightchild=-1;
}
for(i=0;i< n-1;i++)
{
m1=m2=maxvalue;
x1=x2=0;
for(j=0;j< n+i;j++)
{
if(hafftree[j].weight< m1&&hafftree[j].flag==0)
{
m2=m1;
x2=x1;
m1=hafftree[j].weight;
x1=j;
}
else if(hafftree[j].weight< m2&&hafftree[j].flag==0)
{
m2=hafftree[j].weight; x2=j;
}
}
hafftree[x1].parent=n+i;
hafftree[x2].parent=n+i;
hafftree[x1].flag=1;
hafftree[x2].flag=1;
hafftree[n+i].weight=hafftree[x1].weight+hafftree[x2].weight;
hafftree[n+i].leftchild=x1; hafftree[n+i].rightchild=x2;
}
}
void haffmancode(haffnode hafftree[],int n,code haffcode[])
{
code cd; int i,j; int child,parent;
for( i=0;i< n;i++)
{
cd.start=n-1;
cd.weight=hafftree[i].weight;
cd.ch=hafftree[i].ch;
child=i;
parent=hafftree[child].parent;
while(parent!=0)
{
if(hafftree[parent].leftchild==child)
cd.bit[cd.start]=0;
else cd.bit[cd.start]=1;
cd.start--;
child=parent;
parent=hafftree[child].parent;
}
for(j=cd.start+1;j< n;j++)
haffcode[i].bit[j]=cd.bit[j];
haffcode[i].start=cd.start;
haffcode[i].weight=cd.weight;
haffcode[i].ch=cd.ch;
}
}
void ccode(haffnode hafftree[],int n)
{ }
int main( )
{
int n=8;
int weight[]={5,29,7,8,14,23,3,11};
char text[]={'a','b','c','d','e','f','g','h'};
haffnode myhafftree[maxvalue];
code myhaffcode[maxvalue];
haffman(weight,text,n,myhafftree);
haffmancode(myhafftree,n,myhaffcode);
ccode(myhafftree,n);
return 0;
}
输入
根据哈夫曼树编码表，针对字符串做好的编码结果。
输出
对每一行需要解码的串，进行解码，并输出解码后的结果。
样例输入
000100011011101110
样例输出
aabcc
1 const int maxvalue=100; 2 const int maxbit=100; 3 const int maxn=100; 4 #include "iostream" 5 #include "stdio.h" 6 #include "stdlib.h" 7 #include "string.h" 8 using namespace std; 9 struct haffnode 10 { 11 char ch; 12 int weight; 13 int flag; 14 int parent; 15 int leftchild; 16 int rightchild; 17 }; 18 struct code 19 { 20 int bit[maxn]; 21 int start; 22 int weight; 23 char ch; 24 }; 25 void haffman(int weight[],char text[],int n,haffnode hafftree[]) 26 { 27 int j,m1,m2,x1,x2,i; 28 for(i=0; i< 2*n-1; i++) 29 { 30 if(i < n) 31 { 32 hafftree[i].weight=weight[i]; 33 hafftree[i]. 34 ch=text[i]; 35 } 36 else 37 { 38 hafftree[i].weight=0; 39 hafftree[i].ch='#'; 40 } 41 hafftree[i].parent=0; 42 hafftree[i].flag=0; 43 hafftree[i].leftchild=-1; 44 hafftree[i].rightchild=-1; 45 } 46 for(i=0; i< n-1; i++) 47 { 48 m1=m2=maxvalue; 49 x1=x2=0; 50 for(j=0; j< n+i; j++) 51 { 52 if(hafftree[j].weight< m1&&hafftree[j].flag==0) 53 { 54 m2=m1; 55 x2=x1; 56 m1=hafftree[j].weight; 57 x1=j; 58 } 59 else if(hafftree[j].weight< m2&&hafftree[j].flag==0) 60 { 61 m2=hafftree[j].weight; 62 x2=j; 63 } 64 } 65 hafftree[x1].parent=n+i; 66 hafftree[x2].parent=n+i; 67 hafftree[x1].flag=1; 68 hafftree[x2].flag=1; 69 hafftree[n+i].weight=hafftree[x1].weight+hafftree[x2].weight; 70 hafftree[n+i].leftchild=x1; 71 hafftree[n+i].rightchild=x2; 72 } 73 } 74 void haffmancode(haffnode hafftree[],int n,code haffcode[]) 75 { 76 code cd; 77 int i,j; 78 int child,parent; 79 for( i=0; i< n; i++) 80 { 81 cd.start=n-1; 82 cd.weight=hafftree[i].weight; 83 cd.ch=hafftree[i].ch; 84 child=i; 85 parent=hafftree[child].parent; 86 while(parent!=0) 87 { 88 if(hafftree[parent].leftchild==child) 89 cd.bit[cd.start]=0; 90 else 91 cd.bit[cd.start]=1; 92 cd.start--; 93 child=parent; 94 parent=hafftree[child].parent; 95 } 96 for(j=cd.start+1; j< n; j++) 97 haffcode[i].bit[j]=cd.bit[j]; 98 haffcode[i].start=cd.start; 99 haffcode[i].weight=cd.weight; 100 haffcode[i].ch=cd.ch; 101 } 102 } 103 void ccode(haffnode hafftree[],int n) 104 { 105 int i,j=0,m=2*n-1; 106 char b[maxn]; 107 memset(b,'\0',sizeof(b)); 108 i=m-1; 109 scanf("%s",b); 110 while(b[j]!='\0') 111 { 112 if(b[j]=='0') 113 i=hafftree[i].leftchild; 114 else 115 i=hafftree[i].rightchild; 116 if(hafftree[i].leftchild==-1) 117 { 118 printf("%c",hafftree[i].ch); 119 i=m-1; 120 } 121 j++; 122 } 123 } 124 int main( ) 125 { 126 int n=8; 127 int weight[]= {5,29,7,8,14,23,3,11}; 128 char text[]= {'a','b','c','d','e','f','g','h'}; 129 haffnode myhafftree[maxvalue]; 130 code myhaffcode[maxvalue]; 131 haffman(weight,text,n,myhafftree); 132 haffmancode(myhafftree,n,myhaffcode); 133 ccode(myhafftree,n); 134 return 0; 135 }
