GrimePuz.java

import com.google.common.base.Joiner;
import com.google.common.primitives.Ints;
import java.util.Arrays;

public class GrimePuz {
    public static void main(String[] args) {
        int[] n = new int[10];
        int[] counts = new int[10];
        n[0] = 1;
        while (n[0] < 10) {
            for (int i = 0; i < 10; ++i)
                counts[i] = 0;
            for (int i = 0; i < 10; ++i)
                counts[n[i]]++;
            
            if (Arrays.equals(n, counts)) {
                System.out.println(Joiner.on("").join(Ints.asList(n)));
            }

            // move to the next number
            n[9]++;
            for (int j = 9; j >= 1 && n[j] == 10; j--) {
                n[j] = 0;
                n[j-1]++;
            }
        }
    }
}