import java.util.HashMap; import java.util.Map; import java.util.Stack; public class IsValidBrackets { public boolean isValid(String s) { Stack stack = new Stack<>(); Map brackets = new HashMap<>(); brackets.put(')', '('); brackets.put(']', '['); brackets.put('}', '{'); char[] cArr = s.toCharArray(); for (char c : cArr) { if (stack.isEmpty()){ stack.push(c); continue; } char topc = stack.peek(); if (brackets.containsKey(c) && topc == brackets.get(c)) { stack.pop(); }else { stack.push(c); } } return stack.isEmpty(); } public static void main(String[] args) { IsValidBrackets brackets = new IsValidBrackets(); System.out.println(brackets.isValid("()]")); } }