I am getting a StackOverflow error in a hashfunction code but I cannot determine , can someone help me fix it/

Question

I am creating a hash function by myself for my university assignment. My hash function works something like this ... It will take a string as input and add the ASCII values of every character into a integer variable named sum. This is done in the function named hash_func. Then in the function named MYHashfunc I have used recursion to decrease the value of sum such that it can be a value lesser than the size of the array in which I will store data in using my hash function. Since I am using seperate chaining method to resolve collisions , I used a LinkedList array. But I am getting a stack overflow error when the function hash_func is called inside MYhashfunc. The code is given below:-

package hashfunction;

import java.util.LinkedList;
import java.util.Scanner;

public class Hashfunction {

public static int MyhashFUNC(String str,int A){
    int X=0;
    int sum = hash_func(str);
    if(sum<A)
        return sum;
    else{
        X = X+sum%10;
        sum /= 10;
        return(MyhashFUNC(str, A));
    }
}

public static int hash_func(String str) {
    int sum = 0;
    int len = str.length();
    for (int i = 0; i < len; i++) {
        if (str.charAt(i) >= '0' && str.charAt(i) <= '9') {
            sum += (int) str.charAt(i);
        } else if (str.charAt(i) >= 'a' && str.charAt(i) <= 'z' || 
         str.charAt(i) >= 'A' && str.charAt(i) <= 'Z') {
            sum += (int) str.charAt(i);
        }
    }
   return sum;
}

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int N;
    int z;
    N = sc.nextInt();
    String[] str_array = new String[N];
    LinkedList<String>[] l_list = new LinkedList[N];
    for (int i = 0; i < N; i++) {
        l_list[i] = new LinkedList<String>();
    }
    for (int i = 0; i < N; i++) {
        str_array[i] = sc.next();
    }
    for (int i = 0; i < N; i++) {
        z = MyhashFUNC(str_array[i],N);
        if(l_list[z].peek()!="-1"){
                l_list[z].set(z, str_array[i]);
        }
        else{
            l_list[z].add(str_array[i]);
        }
    }

    for (int i = 0; i < N; i++) {
        int size = l_list[i].size();
          for (int j = 0; j < size; j++) {
              System.out.println(l_list[i].get(j));
        }
    }
}
}

Answer 1

In the method

public static int MyhashFUNC(String str,int A){
    int X=0;
    int sum = hash_func(str);
    if(sum<A)
        return sum;
    else{
        X = X+sum%10;
        sum /= 10;
        return(MyhashFUNC(str, A));  // Call again MyhashFUNC with same parameters
    }
}

if sum >= a you enter the else block and you call again the same method with the same parameters. This will generate the StackOverFlow.