409 遞迴字串移除

import java.util.Scanner;
public class JPA409 {
    static Scanner keyboard = new Scanner(System.in);
    public static void main(String args[]) {
        String s, c;
        System.out.print("Input a string: ");
        s = keyboard.nextLine();
        System.out.print("Input a character: ");
        c = keyboard.nextLine();
        System.out.printf("%s\n", removeChar(s, c));
        System.out.print("Input a string: ");
        s = keyboard.nextLine();
        System.out.print("Input a character: ");
        c = keyboard.nextLine();
        System.out.printf("%s\n", removeChar(s, c));
    }

    static String removeChar(String s, String c){
    if(s.equals("")){
    return "";
    }
    else if (s.substring(0,1).equals(c)){
    return removeChar(s.substring(1),c);
    }
    else{
    return s.substring(0,1)+removeChar(s.substring(1),c);
    }
    }
}