查找算法 —— 来自《C++数据结构与程序设计》Robert L.Kruse Alexander J.Ryba

用一个模板类实现二分查找算法。运行时首先按顺序输入到查找的范围，因为是一个测试性的实验，故我们只输入5个数

其中我们要查找一个3，这里读者可以自己改test.h 中的数值检测。

 

基类 List

#ifndef LIST_H#define LIST_H#include "res.h"#include <iostream>using namespace std;template<class T>class List{public:List();int size() const;bool full() const;bool empty() const;void clear() ;void traverse(void (*visit)(T &)) ;Error_code retrieve(int position, T &x)const ;Error_code replace (int position,T & x);Error_code remove(int position,T & x);Error_code insert(int position,const T & x);protected:int count;T entry[max_list];};template<class T>int List<T>::size() const{return count;}template<class T>bool List<T>::full() const{return count == max_list;}template<class T>bool List<T>::empty() const{return count == 0;}template<class T>void List<T>::traverse(void (*visit)(T &)){for (int i = 0;i<count;i++){(*visit)(entry[i]);}}template<class T>Error_code List<T>::retrieve(int position, T &x) const{if (count == 0)return underflow;else{if (position<0||position>max_list){cout<<"Invalid position."<<endl;return false_Operator;}elsex = entry[position];}return success;}template<class T>Error_code List<T>::replace(int position,T & x){if (position<0||position>max_list){cout<<"Invalid position."<<endl;return false_Operator;}else{entry[position] = x;}return success;}template<class T>Error_code List<T>::remove(int position,T & x){if (position<0||position>max_list)return false_Operator;else{x = entry[position];for (int i = position;i<count-1;i++){entry[i] = entry[i+1];}count--}}template<class T>Error_code List<T>::insert(int position,const T & x){if (full()){return overflow;}if (position<0||position>max_list){return false_Operator;}for (int i = count-1;i>position;i--){entry[i+1] =entry[i];}entry[position] = x;count++;return success;}template<class T>List<T>::List(){count = 0;}#endif

派生类 Ordered_list

#ifndef ORDERED_LIST_H#define ORDERED_LIST_Htypedef int Key;typedef int Record;#include "list.h"template<class Record>class Odered_list: public List<Record>{public:Odered_list();Error_code insert(const Record &data);Error_code insert(int position,Record &data);Error_code replace(int position,Record &data);};template<class Record>Odered_list<Record>::Odered_list(){count = 0;}template<class Record>Error_code Odered_list<Record>::insert(const Record &data){int s = size();int positon;for (positon=0;positon<s;positon++){Record list_data;retrieve(positon,list_data);if (data>=list_data){break;}}return List<Record>::insert(positon,data);}template<class Record>Error_code Odered_list<Record>::insert(int position,Record &data){Record list_data;if (position>0){retrieve(position-1,list_data);if(data<list_data)return fail;}if (position<size()){retrieve(position,list_data);if(data>list_data)return fail;}return List<Record>::insert(position,data);}template<class Record>Error_code Odered_list<Record>::replace(int position,Record &data){Record list_data;if (position>0){retrieve(position-1,list_data);if(data<list_data)return fail;}if (position<size()){if(data>list_data)return fail;}return List<Record>::replace(position,data);}#endif

查找 search.h

#include "res.h"#include "ordered_list.h"// the recursive of the binary search ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// Error_code recursive_binary_1(const Odered_list<Record> &the_list,const Key &target, // int bottom,int top,int &position) //{ // Record data; //if (bottom<top) //{ // int mid = (bottom+top)/2; //the_list.retrieve(mid,data); // if(data<target)return recursive_binary_1(the_list,target,mid+1,top,position); //elsereturn recursive_binary_1(the_list,target,bottom,mid,position); //}else if (bottom>top){return not_present; // }else{position = bottom; //the_list.retrieve(bottom,data);if(data==target)return success;elsereturn not_present;}} // // Error_code run_recursive_binary_1( Odered_list<Record> &the_list,const Key &target,int position) //{ // return recursive_binary_1(the_list,target,0,the_list.size()-1,position); //} // ///////////////////////////////////////////////////////////////////////////////////////////////////////////////// the binary search without recursive////////////////////////////////Error_code binary_search( Odered_list<Record> &the_list,const Key &target,int position ) // {Record data;int bottom = 0;int top = the_list.size()-1;while(bottom<top) //{int mid = (bottom+top)/2;the_list.retrieve(mid,data);if(data<target)bottom = mid+1; //elsetop = mid;}if (top<bottom){return not_present; //}else{position = bottom; //the_list.retrieve(bottom,data);if(data==target) return success;else return not_present;}} // //////////////////////////////////////////////////////////////////////////////////////////////////// Recognizing Equalit/////////////////////// /////////////////////////////////////////////// //Error_code recursive_binary_2(const Odered_list<Record> &the_list,const Key &target, // int bottom,int top,int position) //{ //Record data;if (bottom<=top){int mid = (bottom+top)/2; //the_list.retrieve(mid,data);if (data == target){ //position = mid;return success;} //else if (data<target)return recursive_binary_2(the_list,target,mid+1,top,position); //elsereturn recursive_binary_2(the_list,target,bottom,mid-1,position); //}return not_present;} //Error_code run_recursive_binary_2(const Odered_list<Record> &the_list,const Key &target,int &position) //{return recursive_binary_2(the_list,target,0,the_list.size()-1,position); //} ///////////////////////////////////////////////////////////////////////////////////////////////////

额外的定义

#ifndef RES_H#define RES_Henum Error_code {success,overflow,underflow,false_Operator,fail,not_present};const max_list = 30;#endif

测试

#include "ordered_list.h"#include "research.h"#include <iostream>using namespace std;int main(){Odered_list<int> test; test.size();int position1,position2;Record val;cout<<"Please enter a serious number in order: "<<endl;for (int i=0;i<5;i++){cin>>val;test.insert(i,val);}run_recursive_binary_1(test,3,position1);binary_search(test,3,position2);cout<<position2<<"/t"<<position1<<endl;return 0;}