can we do looping inside recursion function

[seninfothil]

hai
i wrote a program for sudoku puzzle .... for that i need to go for recursion function . inside the function i have go for looping.... where i have call the rec..function again..

but it not works... is it possible ...if so how....

[sicarie]

hai
i wrote a program for sudoku puzzle .... for that i need to go for recursion function . inside the function i have go for looping.... where i have call the rec..function again..

but it not works... is it possible ...if so how....

I'm sure you could, here are a couple links on recursion, more than that, it really depends on your implementation.

[Ganon11]

You can implement recursion in many ways. I had to write a recursive function that called itself within a loop. It was horribly inefficient, but necessary to solve the problem.

[sicarie]

Ganon11, did you have a book that you got that from, or are there a few good online links? (Mine's just a google search...)

[Ganon11]

It was actually from a programming competition. Here is the PDF file of all the questions, the one I'm talking about is Question #8. You are also provided with the following code to start with:

import java.io.*;
import java.util.*;
 
/**
 * Compute ways of making change
 *
 * This program computes the number of ways of making change from a
 * given currency system.  
 * 
 * For the UMD High School Programming Contest, 2006.
 * @author Dave Mount
 */
public class Change {
 
    public static void main(String[] args) throws Exception {
 
        /* read input */
        Scanner scanner = new Scanner( System.in );
 
        int nCoins = scanner.nextInt();
        int[] coins = new int[nCoins];
        for (int i = 0; i < nCoins; i++) {
            coins[i] = scanner.nextInt();
        }
        int total = scanner.nextInt();
 
        /* echo input */
        System.out.print("Coins:");
        for (int i = 0; i < nCoins; i++) {
            System.out.print(" " + coins[i]);
        }
        System.out.println("\nTotal: " + total);
 
        /* compute and print result */
        int result = countCombinations(coins, total);
        System.out.println("Number of combinations: " + result);
    }
 
    /** Counts the number of possible coin combinations for given total.
     *  
     *  @param    coins Array containing the coin value (ascending order).
     *  @param    total Total amount of change to make.
     *  @return    The number of combinations.
     */
    private static int countCombinations(int[] coins, int total) {
                int result = 0;
        /* ------------------- INSERT CODE HERE ---------------------*/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
        /* -------------------- END OF INSERTION --------------------*/
                return result;
 
    }
}