#include<iostream> #include<assert.h> using namespace std; struct HuffmanNode {     unsigned int weight;     unsigned int parent,leftChild,rightChild;     HuffmanNode()     {         weight=0;parent=0;leftChild=0;rightChild=0;     } }; void Select(const HuffmanNode* & nodelist,const int length,int & a, int &b) {     int min=1000000,min2=1000000;     for(int i=0;i<length;i++)     {         if(min>nodelist[i].weight&&nodelist[i].parent==0)         {             min=nodelist[i].weight;             a=i;         }     }     for(int j=0;j<length;j++)     {         if(j!=a&&min2>nodelist[j].weight&&nodelist[j].parent==0)         {             min2=nodelist[j].weight;             b=j;         }     } } char ** HuffmanCoding(const int *w, const int n) {     assert(w!=NULL);     int i,min1,min2;     int m = 2*n-1;     HuffmanNode * nodelist = new HuffmanNode[m]();     for(i=0;i<n;i++)     {         nodelist[i].weight=w[i];         nodelist[i].parent=0;     }     for(i=n;i<m;i++)     {         Select(nodelist,i,min1,min2);         nodelist[min1].parent=i;         nodelist[min2].parent=i;         nodelist[i].weight=nodelist[min1].weight+nodelist[min2].weight;         nodelist[i].rightChild=min2;         nodelist[i].leftChild=min1;         nodelist[i].parent=0;     }     char temp [20];     char ** code = new char * [n];     for(i=0;i<n;i++)     {         int j=i;         int index=0;         while(j!=m-1)         {             if(j==nodelist[nodelist[j].parent].leftChild) temp[index++]='0';             else temp[index++]='1';             j=nodelist[j].parent;         }         temp[index]='\0';         code[i] = new char[index+1];         strcpy(code[i],temp);     }     delete nodelist;     return code; } int main() {     const int size=6;     char word[size]={'A','B','C','D','E','F'};//编码字符     int w[size]={4,3,2,1,7,8};//权重     char ** code;     code=HuffmanCoding(w,size);     assert(code!=NULL);     for(int i=0;i<size;i++)     {         cout<<word[i]<<" is coded as "<<code[i]<<endl;     }     //注意二级指针的释放问题     for(int j=0;j<size;j++)     {         delete []code[j];     }     delete []code;     return 0; }