求一个java算法，计算字符串的排序组合方式

Question

public class Composition {
    
    List<String> chars= Arrays.asList("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S"
            ,"T","U","V","W","X","Y","Z");
    // 传入长度n生成n位字符有多少种组合方法 比如传入3 生成abc acd 等等
    public static List<String> generate(int charsLength){
    
    }
}

Answer 1

import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;

public class Main {
    public static void DFS(List<String> chars, String prefix, int max) {
        if (prefix.length() != 0  && max==0) {
            System.out.println(prefix);
            return;
        }

        for (int i = 0; i < chars.size(); i++) {

            List<String> temp = new LinkedList<String>(chars);
            String item = (String) temp.remove(i); // 取出被删除的元素，这个元素当作一个组合用掉了
            DFS(temp, prefix + item, max - 1);
        }
    }

    static List<String> chars = Arrays.asList("A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O",
            "P",
            "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z");

    public static void main(String[] args) {
        DFS(chars, "", 3);
    }

}

算法修改自:https://blog.csdn.net/Mikchy/article/details/91383798