字符二分快速查找

import java.util.Scanner;/** *  * @author luozhonghua * */public class charSearchAndSort { static void kuaiSu(char[] a,int left,int right)             //字符快速排序      {          int f,l,r;          char t;            l=left;          r=right;          f=a[(left+right)/2];                  while(l<r){              while(a[l]<f) ++l;              while(a[r]>f) --r;              if(l<=r){                  t=a[l];                  a[l]=a[r];                  a[r]=t;                  ++l;                  --r;              }          }                  if(l==r)  l++;          if(left<r) kuaiSu(a,left,l-1);                 //递归调用          if(l<right) kuaiSu(a,r+1,right);                //递归调用      }    static int searchFun(char []a,int n,char x){                     //折半查找    int mid,low,high;low=0;high=n-1;    while(low<=high){   mid=(low+high)/2;if(a[mid]==x)            return mid;//找到else if(a[mid]>x)    high=mid-1;        elselow=mid+1;    }return -1;//未找到}     public static void main(String[] args)       {          char[] str=new char[80];          int N;        char[] x=new char[80];          System.out.print("输入一个字符串:");          Scanner input=new Scanner(System.in);          str=input.next().toCharArray();                         //输入字符串          N=str.length;             System.out.print("排序前：\n");          System.out.println(str);                //输出          kuaiSu(str,0,N-1);                      //二分排序          System.out.print("排序后：\n");          System.out.print(str);              //输出           //二分查找        System.out.print("\n");        System.out.println("输入要查找的字符:");    Scanner inpu=new Scanner(System.in);    x=inpu.next().toCharArray();//输入要查找的数   int n=searchFun(str,N,x[0]);//查找    if(n<0)//输出查找结果           System.out.println("没找到数据:"+x);else   System.out.println("数据:"+x[0]+" 位于数组的第"+(n+1)+" 个元素处。");       }  }