searchstudy.java

二分查找的应用

import java.io.*;
import java.util.*;
import java.lang.*;
import java.text.*;

public class SearchStudy {

	/**
	 * @param args
	 */
	
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		
		 Scanner readerfile = new Scanner(System.in);
			System.out.println("Please input the file name:");
			String	f1 = readerfile.next();
		
		try
		{
		BufferedReader in=new BufferedReader(new FileReader(f1));
		Person[] persons = readData(in);
		in.close();
		Arrays.sort(persons);
		int n=persons.length;
		int i = 0, k = 0,p=0;
		k =1000000;
		        
		     p=n;
			
		for (int j=0;j<17;j++)
		{
			 p=(p-1)/2;
			int value =p;
		String keyValue = persons[value].getFirstName();
		System.out.println("keyValue=" + keyValue);
		   Person bi=null;
		double  start = System.currentTimeMillis();
		     	for (i = 0; i < k; i++)
				{
					  	bi = Search.binary(persons, keyValue);
				}
						double time =1000.00*( System.currentTimeMillis() - start);
						double d =1.000*time/k;
				        System.out.printf("The binary table time/k=%10.10f",d);	
					    System.out.println();
			   
		
					    
		}
		}
		catch(IOException exception)
		{
			exception.printStackTrace();
		}
		
		
	}
	
	
	
	 static Person[] readData(BufferedReader in) throws IOException
	 
	{
		
		int 	n= 100000;
		Person[] persons=new Person[n];
		for (int i=0;i<n;i++)
		{
			persons[i]=new Person();
			persons[i].readData(in);
		}
		return persons;
	}
	 

	 
	 
}