make code readable

Author: realDuYuanChao

DataStructures/Stacks/BalancedBrackets.java

@@ -62,7 +62,7 @@ public static boolean isBalanced(String brackets) {
  case ')':
  case ']':
  case '}':
- if (!(!bracketsStack.isEmpty() && isPaired(bracketsStack.pop(), bracket))) {
+ if (bracketsStack.isEmpty() || !isPaired(bracketsStack.pop(), bracket)) {
  return false;
  }
  break;