write a program that will remove all occurrences of the second string from the first string.

import java.util.Scanner;

class removesubstring
{
static void getarr(String str, int arrry1[])
{
int n = str.length();
int k,s = 0,l = 0;
for (int i = 1; i < n; i++) {
if (i > l) {
s = l = i;
while (l < n && str.charAt(l - s) == str.charAt(l))
{
l++;
}
arrry1[i] = l - s;
l--;
}
else {
k = i - s;
if (arrry1[k] < l - i + 1) {
arrry1[i] = arrry1[k];
}
else {
s = i;
while (l < n && str.charAt(l - s) == str.charAt(l)) {
l++;
}
arrry1[i] = l - s;
l--;
}
}
}
}
static String removestr(String str, String word) {
String concat = word + "$" + str;
int l = concat.length();
int []r = new int[l];

    getarr(concat, r);
    String res="";
    int Size = word.length();

    for (int i = 0; i < l; ++i) {
        if (i + Size < l - 1 && r[i + Size + 1] == Size) {
            i += Size - 1;
        }
        else if (i < str.length()) {
            res += str.charAt(i);
        }
    }
    return res;
}
public static void main(String[] args)
{
    Scanner sc=new Scanner(System.in);
    System.out.println("enter the string");
    String str = sc.nextLine();
    System.out.println("enter string to remove");
    String substring = sc.nextLine();

    System.out.print(removestr(str, substring));
}

}