combination

gistfile1.txt

import java.util.Arrays;

public class TestAnything {

    public static void main(String[] args) throws Exception {
        int[] seqs = new int[] { 1, 2, 3, 4, 5, 6 };
        
        int[] pointers = new int[] { 0, 1, 2 };

        while (!isExhausted(pointers, seqs.length)) {
            System.out.println(Arrays.toString(pointers));
            updatePointers(pointers, seqs.length, pointers.length - 1);
        }

    }

    private static boolean isExhausted(int[] pointers, int length) {
        for (int i = pointers.length - 1; i >= 0; i--) {
            if (pointers[i] != length - (pointers.length - i)) {
                return false;
            }
        }
        return true;
    }

    private static void updatePointers(int[] pointers, int length, int curPos) {
        if (pointers[curPos] + 1 <= length - 1) {
            pointers[curPos]++;
        } else {
            updatePointers(pointers, length - 1, curPos - 1);
            pointers[curPos] = pointers[curPos - 1] + 1;
        }
        return;
    }
}