nextperm results

Problem: NEXTPERM
State: Wrong Answer
Total score for this submission: 0
Test Case #0 for 2 points
Wrong Answer
Runtime: 0.12
Test Case #1 for 2 points
Wrong Answer
Runtime: 0.124
Test Case #2 for 2 points
Wrong Answer
Runtime: 0.124
Test Case #3 for 2 points
Wrong Answer
Runtime: 0.12
Test Case #4 for 2 points
Wrong Answer
Runtime: 0.116
Test Case #5 for 2 points
Wrong Answer
Runtime: 0.124
Test Case #6 for 2 points
Wrong Answer
Runtime: 0.124
Test Case #7 for 2 points
Wrong Answer
Runtime: 0.14
Test Case #8 for 2 points
Wrong Answer
Runtime: 0.108
Test Case #9 for 2 points
Wrong Answer
Runtime: 0.124
/**
 * Created by aditya on 16-10-2014.
 */

import java.io.BufferedInputStream;
import java.util.ArrayList;
import java.util.Scanner;

public class Main {
    public static void main(String args[]) {
        Scanner scan = new Scanner(new BufferedInputStream(System.in));
        int n = scan.nextInt();
        int k = scan.nextInt();
        ArrayList<Integer> list = new ArrayList<Integer>(k);
        ArrayList<Integer> list_out = new ArrayList<Integer>(k);
        for (int i = 0; i < k; i++) {
            list.add(scan.nextInt());
        }
        for (int j = 0; j < k; j++) {
            list_out.add(next_perm(list.get(j), n));
        }
        for (int temp : list_out) {
            System.out.println(temp);
        }
        System.out.flush();
    }

    public static int next_perm(int k, int n) {
        int perm = 0;
        int number = k;
        int num[] = new int[n];
        for (int i = 0; i < n; i++) {
            num[i] = number % 10;
            number /= 10;
        }
        int k_max = 0;
        for (int i = 0; i < n; i++) {
            if (i == (n-1))
                break;
            if (num[i + 1] >= num[i]) {
                ++k_max;
            } else if (num[i + 1] < num[i]) {
                break;
            }
        }
        if(k_max==(n-1))return k;
        int j_max = k_max+1;
        for (int i = k_max; i >= 0; i--) {
            if (num[i] > num[k_max + 1]) {
                --j_max;
            } else {
                break;
            }
        }
        int temp=num[j_max];
        num[j_max]=num[k_max+1];
        num[k_max+1]=temp;
        for(int i=k_max,j=0;i>j;i--,j++){
            int tempo = num[i];
            num[i]=num[j];
            num[j]=tempo;
        }
        for (int i = 0; i < n; i++) {
            perm += num[i] * (int) Math.pow(10, i);
        }
        return perm;
    }
}