permutations

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package javaapplication1;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 *
 * @author Islom
 */
public class JavaApplication1 {

//    static List<List<Integer>> permutations = new ArrayList<List<Integer>>();
    static List<Integer> result = new ArrayList<>();
  
  // arguments are passed using the text field below this editor
  public static void main(String[] args)
  {
    ArrayList<Integer> first = init2(4);
    ArrayList<Integer> second = init2(4);
//    ArrayList<Integer> third = init2(3);
    
    
    List<List<Integer>> lists = new ArrayList<>();
    lists.add(first);
    lists.add(second);
//    lists.add(third);
    
    GeneratePermutations(lists, 0, 0);
       
    System.out.println("End"); 
  }
  
  static ArrayList<Integer> init(int n){
        ArrayList<Integer> res = new ArrayList<>();
        
        for(int i = 1; i <= n; i++){
            res.add(i);
        }
        
        return res;
  }
  
  static ArrayList<Integer> init2(int n){
        ArrayList<Integer> res = new ArrayList<>();
        
        for(int i = 0; i <= n; i++){
            res.add(i);
        }
        
        return res;
  }
  
  static void GeneratePermutations(List<List<Integer>> Lists, int depth, Integer sum)
{
   
    if(depth == Lists.size())
    {        
       
        if(sum == 4){
            for(Integer cur: result){
                System.out.print(cur + " "); 
            }
        
            System.out.print("sum: " + sum); 
       
            System.out.println();
        }
       
      
//     result.clear();
       return;
    }         

    for(int i = 0; i < Lists.get(depth).size(); ++i)
    {
        if(result.size() > depth){
            result.set(depth, Lists.get(depth).get(i));
        } else {
            result.add(depth, Lists.get(depth).get(i));
        }               
        
        GeneratePermutations(Lists, depth + 1, sum + Lists.get(depth).get(i));
    }
}
    
}