實驗要求

1. 用隨機數產生100個待查詢資料元素的關鍵字值。

2. 測試下列各排序函式的機器實際執行時間：

   （1）順序查詢
   （2）二叉排序樹查詢
   （3）折半查詢

提示：
（1）和（2）使用同樣的實驗資料；（3）要求資料元素必須有序，故需要先使用排序演算法進行排序（可以使用氣泡排序）

程式程式碼

#include <bits/stdc++.h>
#define nmax 100
#define maxtime 5000000
#define EQ(a,b) ((a) == (b))
#define LT(a,b) ((a) < (b))
#define LQ(a,b) ((a) <= (b))
 

#define ElemType int
#define KeyType int
#define TElemType int
#define Status int
#define ERROR 0
#define OK 1
#define FALSE 0
#define TRUE 1
using namespace std;
int cnt = 0;
typedef struct{
    ElemType *elem;
    int length;
}SSTable;
typedef struct BiTNode{
    TElemType data;
    struct BiTNode * lchild, * rchild;
}BiTNode, *BiTree
 
;
int Search_Seq(SSTable ST, KeyType key)
{
    ST.elem[0] = key;
    int i;
    for(i=ST.length;!EQ(ST.elem[i],key);--i);
    return i;
}
void init(SSTable &st)
{
    st.elem = (int*)malloc(sizeof(int) * (nmax)+1);
    st.length = nmax;
    srand((int)time(NULL));
    for(int i = 1; i<=nmax;++i){
        st.elem[i] = rand
 
()%500;
    }
}
int Search_Bin(SSTable st, KeyType key)
{
    int low = 1, high = st.length;
    while(low<=high){
        int mid = (low + high) /2;
        if(EQ(key,st.elem[mid])) return mid;
        else if(LT(key,st.elem[mid])) high = mid-1;
        else low = mid+1;
    }
    return 0;
}
Status SearchBST(BiTree T,KeyType key, BiTree f, BiTree & p)
{
    if(!T) {p = f; return false;}
    else if(EQ(key,T->data)) { p = T;return true;}
    else if(LT(key,T->data)) return SearchBST(T->lchild,key,T,p);
    else return SearchBST(T->rchild,key,T,p);
}
int Search_Bin_None(SSTable st, KeyType key,int low , int high)
{
    int mid = (low+high)/2;
    if(low>=high) return ERROR;
    if(EQ(key,st.elem[mid])) return mid;
    else if(LT(key,st.elem[mid])) return Search_Bin_None(st,key,low,mid-1);
    else return Search_Bin_None(st,key,mid+1,high);
}
void printtime(double start, double finish,int &cnt )
{
    double duration;
    duration = (double)((finish - start) / CLOCKS_PER_SEC);
    printf("總共耗時%f秒\n",duration);
    printf("其中查詢成功%d次\n查詢失敗%d次\n\n",cnt,maxtime - cnt);
    cnt = 0;
}
Status InsertBST(BiTree & T, ElemType e)
{
    BiTree p;
    if(!SearchBST(T,e,NULL,p)){
        BiTree s = (BiTree) malloc(sizeof(BiTNode));
        s->data = e; s->lchild = s->rchild = NULL;
        if(!p) T = s;
        else if(LT(e,p->data)) p->lchild = s;
        else p->rchild = s;
        return true;
    }
    else return false;
}
void InorderTraverse(BiTree T)
{
    if(T){
        InorderTraverse(T->lchild);
        cnt++;
        printf("%d ",T->data);
        if(cnt %10 ==0)  printf("\n");
        InorderTraverse(T->rchild);
    }
}
void findelem(SSTable st,BiTree T)
{
    init(st);
    double start = 0,finish = 0;
    printf("順序查詢%d次的情況\n",maxtime);
    start = clock();
    int cnt = 0;
    for(int i = 0; i<maxtime;++i){
        if(Search_Seq(st,(i+(rand()%100)/3+1)%750)!=0)
            cnt++;
    }
    finish = clock();
    printtime(start,finish,cnt);

    printf("二分查詢（非遞迴）%d次的情況\n",maxtime);
    sort(st.elem,st.elem+nmax);
    start = clock();
    for(int i = 0; i<maxtime;++i){
        if(Search_Bin(st,(i+(rand()%100)/3+1)%750)){
            cnt++;
        }
    }
    finish = clock();
    printtime(start,finish,cnt);

    printf("二分查詢（遞迴）%d次的情況\n",maxtime);
    start = clock();
    for(int i = 0; i<maxtime;++i){
        if(!Search_Bin_None(st,(i+(rand()%100)/3+1)%750,1,st.length)){
            cnt++;
        }
    }
    finish = clock();
    printtime(start,finish,cnt);

    printf("二叉排序樹查詢%d次的情況\n",maxtime);
    for(int i = nmax/2;i>=0;--i){
        InsertBST(T,st.elem[nmax/2-i]);
        InsertBST(T,st.elem[nmax/2+i]);
    }
    printf("二叉排序樹中序遍歷結果為\n",maxtime);
    InorderTraverse(T);
    printf("\n");
    for(int i = 0; i<maxtime;++i){
        if(InsertBST(T,(i+(rand()%100)/3+1)%750)){
            cnt++;
        }
    }
    finish = clock();
    printtime(start,finish,cnt);
}
int main()
{
    SSTable st;
    BiTree T = (BiTree)malloc(sizeof(BiTNode));
    T->lchild = T->rchild = NULL;
    init(st);
    findelem(st,T);
    return 0;
}

執行結果