用eclipse运行算法第四版的BinarySearch

import java.util.Arrays;

import edu.princeton.cs.algs4.In;
import edu.princeton.cs.algs4.StdIn;
import edu.princeton.cs.algs4.StdOut;


/**
 *  The {@code BinarySearch} class provides a static method for binary
 *  searching for an integer in a sorted array of integers.
 *  

 *  The indexOf operations takes logarithmic time in the worst case.
 *  

 *  For additional documentation, see Section 1.1 of
 *  Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.
 *
 *  @author Robert Sedgewick
 *  @author Kevin Wayne
 */
public class BinarySearch {

    /**
     * This class should not be instantiated.
     */
    private BinarySearch() { }

    /**
     * Returns the index of the specified key in the specified array.
     *
     * @param  a the array of integers, must be sorted in ascending order
     * @param  key the search key
     * @return index of key in array {@code a} if present; {@code -1} otherwise
     */
    public static int indexOf(int[] a, int key) {
        int lo = 0;
        int hi = a.length - 1;
        while (lo <= hi) {
            // Key is in a[lo..hi] or not present.
            int mid = lo + (hi - lo) / 2;
            if      (key < a[mid]) hi = mid - 1;
            else if (key > a[mid]) lo = mid + 1;
            else return mid;
        }
        return -1;
    }

    /**
     * Returns the index of the specified key in the specified array.
     * This function is poorly named because it does not give the rank
     * if the array has duplicate keys or if the key is not in the array.
     *
     * @param  key the search key
     * @param  a the array of integers, must be sorted in ascending order
     * @return index of key in array {@code a} if present; {@code -1} otherwise
     * @deprecated Replaced by {@link #indexOf(int[], int)}.
     */
    @Deprecated
    public static int rank(int key, int[] a) {
        return indexOf(a, key);
    }

    /**
     * Reads in a sequence of integers from the whitelist file, specified as
     * a command-line argument; reads in integers from standard input;
     * prints to standard output those integers that do not appear in the file.
     *
     * @param args the command-line arguments
     */
    public static void main(String[] args) {

        // read the integers from a file
        In in = new In(args[0]);
        int[] whitelist = in.readAllInts();

        // sort the array
        Arrays.sort(whitelist);

        // read integer key from standard input; print if not in whitelist
        while (!StdIn.isEmpty()) {
            int key = StdIn.readInt();
            if (BinarySearch.indexOf(whitelist, key) == -1)
                StdOut.println(key);
        }
    }
}

　　这是代码，官网上最新的代码。课本上的有一点错误。

0.将algs4.jar添加到环境变量

 

 

 

 我是新建了一个文件夹algs4,在里面存放了algls4.jar 和 algs4-date两个文件

将algs4.jar包所在的地址添加到classpath后面。

 

1.引入algs4.jar

 

 右键点击工程文件，我这里是BinarySearch,然后选中properties.

 

再选中java build path, libraries。

 

 

 

 

 右击classpath，点击add extern jars

 

打开algs4.jar所在的地址 

选中algs4.jar即可。这样就导入了algs4.jar这个包.

 

2.使用eclipse的run as 进行重定向

 

 

 

 

 

 

 

 注意：这里的input file地址：是要输入的文件的地址。

 

 点击隐藏的选项卡，选中argument

 

 

 

 

 在program argument中填入largeW.txt(白名单)

然后运行即可.

特别注意：

 

 此处我的largeW.txt和largeT.txt在同一个文件夹里。也就是说代码工程文件里放了largeT.txt和largeW.txt文件