how to solve this error ? poj.org 3461 Oulipo Java

general
1

I thought that I did solved the problem Oulipo 3461 -- Oulipo , but I have RuntimeError in my solution and I can’t to solve the problem. Why my solution is wrong? an idea to improve my solution?

Here is the code
(Thanks!)

import java.util.Scanner;

public class Main {

public static void main(String[] args) {

    Scanner in = new Scanner(System.in);
    int cant = in.nextInt();
    in.nextLine();
    for (int i = 0; i < cant; i++) {
        int cont = 0;
        String co = in.nextLine();
        String pal = in.nextLine();
        char let = co.charAt(0);
        int l1 = co.length();
        int l2 = pal.length();
        for (int j = 0; j < l2 - l1 + 1; j++) {
            boolean es = true;
            boolean es1 = true;
            if (pal.charAt(j) == let) {
                int k;
                int nuevoind = 0;
                int pAux = 0;
                for (k = 0; k < l1; k++) {
                    if (k > 0) {
                        if ((pal.charAt(j + k) == co.charAt(nuevoind))) {
                            nuevoind++;
                            pAux = k;
                            es1 = true;
                        } else {
                            nuevoind = 0;
                            es1 = false;
                        }
                    }
                    if (pal.charAt(j + k) != (co.charAt(k))) {
                        es = false;
                        if (es1) {
                            j = j + pAux;
                        }
                        break;
                    }
                }
                if (!es) {
                    j = j + pAux-1;
                }

                if (es) {
                    cont++;
                }
            }
        }
        System.out.println(cont);
    }

}

}