#!/usr/bin/env python
 
#Title: N-dimensional loop iterator
#Submitter: Philip Nunez
#Last Updated: 2001/11/01
 
#Description:
#Do nested for loops on an arbitrary list of iterable things.
#Found at: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/84739
class nloop:
    def __init__(self,*varg):
        self.list = list(varg)
        self.iter_list = []
 
        self.memo = [None] * len(self.list)
        if len(self.list):
            self.n_iter(0, self.list)
 
    def __getitem__(self,index):
        return self.iter_list[index]
 
    def n_iter(self,index,stack):
        x = stack[index]
        for i in x:
            self.memo[index] = i
            if index == len(stack) - 1:
                self.iter_list.append(tuple(self.memo))
            else:
                self.n_iter(index + 1, stack)
 
if __name__ == '__main__':
    for tup in nloop(list("abc"),
                     list(range(1,5)),
                     list("def"),
                     list(range(5,10)),
                     list("xyz")):
        print tup

package com.krisneuharth.examples;
 
import java.util.ArrayList;
import java.util.List;
 
@SuppressWarnings("unchecked")
 
// Author: Kris Neuharth
// Ported directly from Python source found at:
// http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/84739
// Tried to keep it as close to the original and generic as possible
public class LoopIterator
{
	// Initialize generic lists
	List list;
	List iter_list;
	List memo;
 
	// Constructor
	public LoopIterator(List lol)
	{
		// Initialize lists
		this.list = lol;
		this.iter_list = new ArrayList();
 
		// Find number of expected values
		int expected = 1;
		for(Object list : this.list)
			expected *= ((List)list).size();
 
		// Test
		if(false)
		{
			System.out.println("\n-- Loop Iterator --");
			System.out.println("Size: " + this.list.size());
			System.out.println("Contents: " + this.list.toString());
			System.out.println("Expected Combinations: " + expected + "\n");
		}
 
		// Create buffer as big as list of lists, init elements to null
		this.memo = new ArrayList();
		for(int ii = 0; ii < this.list.size(); ii++)
			this.memo.add(ii, null);
 
		// If the list of lists has more than one list,
		// process it
		if(this.list.size() > 0)
			n_iter(0, this.list);
	}
 
	// Recursive method to generate combinations from all lists
	public void n_iter(int index, List> stack)
	{
		List x = stack.get(index);
 
		for(String i : x)
		{
			this.memo.set(index, i);
			if(index == stack.size() - 1)
				this.iter_list.add(new ArrayList(this.memo));
			else
				this.n_iter(index + 1, stack);
		}
	}
 
	// Utility method to display the combinations
	public void display()
	{
		int ii = 1;
		for(Object str : this.iter_list)
		{
			System.out.println((ii++) + "\t" +  str.toString());
		}
	}
 
        // Utility method to get the list of combinations for further
	// processing
	public List getCombinations()
	{
		return this.iter_list;
	}
 
	// Driver
	public static void main(String[] args)
	{
		// Create data
		List list1 = new ArrayList();
		list1.add("a");
		list1.add("b");
		list1.add("c");
 
		List list2 = new ArrayList();
		list2.add("1");
		list2.add("2");
		list2.add("3");
 
		List list3 = new ArrayList();
		list3.add("w");
		list3.add("x");
		list3.add("y");
 
		List list4 = new ArrayList();
		list4.add("4");
		list4.add("5");
		list4.add("6");
 
		// Create list of lists
		List lol = new ArrayList();
		lol.add(list1);
		lol.add(list2);
		lol.add(list3);
		lol.add(list4);
 
		// Create loop iterator
		LoopIterator li = new LoopIterator(lol);
 
		// Display results
		for(Object obj : li.getCombinations())
		{
			for(Object oj : (ArrayList)obj)
				System.out.print(oj + " ");
			System.out.println();
		}
	}
}