SecondSearchOptionalTree

#define N 9#include<stdio.h>#include<stdlib.h>#include<stack>struct ElemType{char key;int weight;};struct SSTable{ElemType *elem;int length;};typedef struct BiTNode{ElemType e;BiTNode* lchild;BiTNode* rchild;}*SOSTree;void CreateSSTable(SSTable &st,ElemType R[],int len){st.elem=(ElemType*)malloc(sizeof(ElemType)*(len+1));if(!st.elem){printf("内存分配失败\n");return;}st.length=len;for(int i=1;i<=len;i++)st.elem[i]=R[i-1];}void findSW(int sw[],SSTable st){sw[0]=0;for(int i=1;i<=st.length;i++)sw[i]=sw[i-1]+st.elem[i].weight;}bool Search(SOSTree T,int key){if(T==NULL)return false;while(T){if(T->e.key==key){printf("%3c%3d\n",T->e.key,T->e.weight);return true;}if(T->e.key>key)T=T->lchild;else T=T->rchild;}return false;}void SecondOptional(SOSTree &T,ElemType elem[],int sw[],int low,int high){int i=low;int min=abs(sw[high]-sw[low]);int dw=sw[high]+sw[low-1];for(int j=low+1;j<=high;j++){if(abs(dw-sw[j]-sw[j-1])<min){i=j;min=dw-sw[j]-sw[j-1];}}T=(BiTNode*)malloc(sizeof(BiTNode));T->e=elem[i];if(i==low)T->lchild=NULL;else SecondOptional(T->lchild,elem,sw,low,i-1);if(i==high)T->rchild=NULL;else SecondOptional(T->rchild,elem,sw,i+1,high);}void CreateSOSTable(SOSTree &T,SSTable st){int sw[N+1];if(st.length==0)T=NULL;else{findSW(sw,st);SecondOptional(T,st.elem,sw,1,st.length);}}void PreOrderTraverse(SOSTree T){std::stack<SOSTree> stack;while(T||!stack.empty()){if(T){printf("%3c%3d",T->e.key,T->e.weight);stack.push(T);T=T->lchild;}else{T=stack.top();stack.pop();T=T->rchild;}}}void main(){SSTable st={NULL,0};SOSTree T=NULL;char s;ElemType R[N]={{'A',1},{'B',1},{'C',2},{'D',5},{'E',3},{'F',4},{'G',4},{'H',3},{'I',5}};CreateSSTable(st,R,N);CreateSOSTable(T,st);PreOrderTraverse(T);printf("\n请输入要查找的元素\n");scanf("%c",&s);bool flag=Search(T,s);if(!flag) printf("查找关键字不存在");}