C++第16周项目3 -电子词典

#include <fstream>
#include<iostream>
#include<string>
#include<cstdlib>
using namespace std;

//定义学生类
class Word
{
public:
	void set(string e, string c, string wc);
	int compare(string);  //英语部分与给定字符串比较，等于返回，大于返回，小于返回-1
	void display();
private:
	string english;
	string chinese;
	string word_class;
};

void Word::set(string e, string c, string wc)
{
	english=e;
	chinese=c;
	word_class=wc;
}

void Word::display()
{
	cout<<english<<'\t'<<word_class<<'\t'<<chinese<<endl<<endl;
}

int Word::compare(string k)
{
	return english.compare(k);
}

int BinSeareh(int low, int high, Word *w, string k);

int main( )
{
	Word words[8000]; //用于保存词库
	string e,c,wc;
	string key;      //查询关键词
	int wordsNum=0;  //词库中词数

	//将文件中的数据读入到对象数组中
	ifstream infile("dictionary.txt",ios::in);  //以输入的方式打开文件
	if(!infile)       //测试是否成功打开
	{
		cerr<<"open error!"<<endl;
		exit(1);
	}
	while (!infile.eof())
	{
		infile>>e>>c>>wc;
		words[wordsNum].set(e, c, wc);
		++wordsNum;
	}

	//输入待查关键词并用二分查找法进行查询
	do
	{
		cout<<"请输入待查询的关键词（英文）,0000结束："<<endl;
		cin>>key;
		if (key!="0000")
		{
			int low=0,high=wordsNum-1;  //置当前查找区间上、下界的初值
			int index=BinSeareh(low, high, words, key);
			if (index == -1)
				cout<<"查无此词！"<<endl<<endl;
			else
				words[index].display();
		}
	}
	while(key!="0000");
	cout<<"欢迎再次使用！"<<endl<<endl;
	return 0;
}

int BinSeareh(int low, int high, Word *w, string k)
{
	int mid;
	while(low<=high)
	{
		mid=(low + high) / 2;
		if(w[mid].compare(k)==0)
		{
			return mid; //查找成功返回
		}
		if(w[mid].compare(k)>0)
			high=mid-1; //继续在w[low..mid-1]中查找
		else
			low=mid+1; //继续在w[mid+1..high]中查找
	}
	return -1; //当low>high时表示查找区间为空，查找失败
}