Duplicate Brackets

 

((a + b) + (c + d)) -> false (a + b) + ((c + d)) -> true

import java.util.Stack;

public class Duplicate_Brackets {
    public static void main(String[] args) {
        String str = "(a+b)+((a+b))";
        System.out.println(duplicateBracket(str));
    }

    private static boolean duplicateBracket(String str) {
        char[] arr = str.toCharArray();
        Stack<Character> stack = new Stack<>();
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] != ')')
                stack.push(arr[i]);
            else {
                if (stack.peek() == '(')
                    return true;
                while (stack.peek() != '(')
                    stack.pop();
                stack.pop();
            }
        }
        return false;
    }


}