各位大神求看继续是查找的问题 - 黑马程序员技术交流社区

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
public class ListDemoC {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
List<String> arraylist = new ArrayList<String>();
arraylist.add("java");
arraylist.add("hello");
arraylist.add("www");
// maxShow();
int i1 =myHalfSearch(arraylist,"ww",new mycomHalf());
System.out.println(arraylist);
System.out.println(i1);
Collections.sort(arraylist, new mycomHalf());
System.out.println(arraylist);
}
public static void maxShow(){//原先的折半查找
List<String> al = new ArrayList<String>();
al.add("java");
al.add("hello");
al.add("www");
String s = Collections.max(al);
int i = Collections.binarySearch(al, "java");
System.out.println(al);//打印最大值
System.out.println(i);//打印角标数
}
//制造我自己的折半查找的方法
public static int myHalfSearch(List<String> list,String key,mycomHalf com){
int max,min,mid;
max = list.size()-1;
min=0;
while(min<=max){
mid=(max+min)>>1;//这句话相当于相加除以2
//获取到中间的角标
String s = list.get(mid);//已经获取到中间角标
int num= com.compare(s, key);//比较一下
if(num>0){
max = mid-1;
}
else if(num<0){
min = mid+1;
}
else{
return mid;
}
}
return -min-1;//返回插入点-1
}
}
class mycomHalf implements Comparator<String>{//我自己的比较器
public int compare(String s1, String s2) {
return new Integer(s1.length()).compareTo(new Integer(s2.length()));//按照长度进行比较
// TODO Auto-generated method stub
}
}

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