package data_structures.Stacks;

import java.util.Scanner;
import java.util.Stack;

/**
 *
 * The nested brackets problem is a problem that determines if a sequence of
 * brackets are properly nested. A sequence of brackets s is considered properly
 * nested if any of the following conditions are true: - s is empty - s has the
 * form (U) or [U] or {U} where U is a properly nested string - s has the form
 * VW where V and W are properly nested strings For example, the string
 * "()()[()]" is properly nested but "[(()]" is not. The function called
 * is_balanced takes as input a string S which is a sequence of brackets and
 * returns true if S is nested and false otherwise.
 *
 * @author akshay sharma
 * @date: 2017-10-17
 * @author khalil2535
 *
 */
class BalancedBrackets {

    /**
     *
     * @param s
     * @return
     */
    static boolean is_balanced(String s) {
        Stack bracketsStack = new Stack();
        char[] text = s.toCharArray();
        for (char x : text) {
            switch (x) {
                case '{':
                case '':
                    if (bracketsStack.peek() == '