算法1

Java 代码

import java.io.*; 
import java.util.*;

public class Main {
    static int n;
    static int[] path;
    static boolean[] st;

    public static void main(String[] args) throws Exception{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String s = br.readLine();
        n = Integer.valueOf(s);
        path = new int[n];
        st = new boolean[n+1];
        dfs(0);
    }

    private static void dfs(int u){
        if(u == n){
            for(int i = 0; i < n; i++){
                System.out.print(path[i]+" ");
            }
            System.out.println();
            return;
        }else{
            for(int i = 1; i <= n; i++){
                if(!st[i]){
                    path[u] = i;
                    st[i] = true;
                    dfs(u+1);
                    st[i] = false;
                }
            }
        }
    }
}