Balanced Brackets

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There are 3 kinds of Brackets: [] {} (). Given a String of characters, check if all the brackets in the String are Balanced. A string is balanced if all the start and end brackets are in a correct order so they match each other.

Here are some balanced Strings:

{}
(hello)[world]
[({}{}{})([])]

Here are some Unbalanced ones:

(hello - no ending )
([)] - The [ is improperly enclosed in the ().
)( There's an ending ) without a ( before it.

I/O Format
The first line of input contains a number t. t lines of text follow. Print true if a line is balanced and false otherwise. Print each result on its own line.

Challenge

Given a String, print true if the its balanced and false otherwise.

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Comments

mike

Aug 15, 5:07 PM

This one worked, wdyt?

public static void doStuff(String text){
Stack stack = new Stack<>();

    for (int i = 0; i < text.length(); i++) {

cont...

      char curr = text.charAt(i);
      if(isOpenning(curr)){
        stack.push(curr);
      } else {
        char closingForCurr = getClosingFor(curr);
        if(closingForCurr != ' '){
          if(stack.empty()){
            System.out.println("false");
            return;
          }
          if(stack.peek() == closingForCurr){
            stack.pop();
          } else {
            System.out.println("false");
            return;
          }
        }
      }
    }

    if(stack.empty()){
      System.out.println("true");
    } else {
      System.out.println("false");
    }
}

public static char getClosingFor(char ch){
    if(ch == '}') return '{'; else
    if(ch == ']') return '['; else
    if(ch == ')') return '('; else
  return ' ';
}

public static boolean isOpenning(char aChar){
    return aChar == '{' ||  aChar == '[' || aChar == '(';
}