试题 算法提高 递归倒置字符数组

Sample 1
5 abcde
Sample 2
1 a

Sample 1
ebcda
edcba
edcba
Sample 2
a

import java.util.*;
public class diguidaozhi {

	/**
	 * @param args
	 * 试题 算法提高 递归倒置字符数组
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n =sc.nextInt();
		String str = sc.next();
		StringBuilder jieguo = new StringBuilder();
		System.out.println(result(str,jieguo));;
	}
	static StringBuilder result(String str,StringBuilder jieguo){
		if (str.length()==1) {
			jieguo.append(str);
			return jieguo;
		}else {
			jieguo.append(str.charAt(str.length()-1));
			result(str.substring(0,str.length()-1),jieguo);
			return jieguo;
		}
		
	}

}

import java.util.*;
public class dgdzzfsz {

	/**
	 * @param args
	 * 试题 算法提高 递归倒置字符数组
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		char[] list = new char[n];
		String str = sc.next();
		//将字符串录入字符数组
		for (int i = 0; i < str.length(); i++) {
			list[i] = str.charAt(i);
		}
		zhuanzhi(list,0,list.length-1);
	}
	
	static void zhuanzhi(char[] list,int i,int j){
		//如果长度为1，直接返回
		if (list.length==1) {
			System.out.println();
			System.out.println(list[0]);
		}else {
			//首尾交换
			if (i<list.length/2) {
				char temp = list[j];
				list[j]=list[i];
				list[i]=temp;
				System.out.println(list);
				i++;
				zhuanzhi(list,i,list.length-i-1);
			}else {
				System.out.println();
				System.out.println(list);
			}
		}
	}

}