C++ LinkedStack::isEmpty方法代码示例

bool is_balanced(string brackets)
{
  if(brackets == "") return true;
  LinkedStack ls;
  for (unsigned i = 0; i < brackets.size() ; i++)
  {
    string c = brackets.substr(i,i+1);
    if(c == "[" || c == "(" || c == "{")
    {
      ls.push(c);
    }
    else if(c == "]" )
    {
      if(ls.top() == "[")
      {
        ls.pop();
      }
      else return false;
    }
    else if(c == "}")
    {
      if(ls.top() == "{")
      {
        ls.pop();
      }
    }
    else if( c == ")" )
    {
      if(ls.top() == "(")
      {
        ls.pop();
      }
      else return false;
    }
    else 
    {
      if(ls.isEmpty()) return true;
    }
  }
  if(ls.isEmpty()) return true;
  return false;
}

int main()
{ LinkedStack<int> numbers;
  try 
  { for (int i=10; i < 100; i+=10) numbers.push(i);
    while (!numbers.isEmpty()) cout << numbers.pop() << endl;
    numbers.pop();  
  }  
  catch(StackEmptyException e)
  {  cerr << e;
     return 1;
  }  
  return 0;    
}    

int main() {

	LinkedStack<int> testLinkedStack;

	std::cout << "testLinkedStack.isEmpty() : " << testLinkedStack.isEmpty() << std::endl;
	std::cout << "testLinkedStack.getAllocatedSize() : " << testLinkedStack.getAllocatedSize() << std::endl;
	std::cout << "testLinkedStack.getSize() : " << testLinkedStack.getSize() << std::endl;

	testLinkedStack.push(5);
	testLinkedStack.push(6);
	testLinkedStack.push(7);
	testLinkedStack.push(9);
	testLinkedStack.push(10);

	std::cout << testLinkedStack.peek() << std::endl;

	int a = testLinkedStack.peek();
	testLinkedStack.pop();
	std::cout << a << std::endl;

	std::cout << testLinkedStack.peek() << std::endl;

	a = testLinkedStack.peek();
	testLinkedStack.pop();
	//testLinkedStack.pop(a);
	std::cout << a << std::endl;

	std::cout << testLinkedStack.peek() << std::endl;

	LinkedStack<int> testLinkedStack_2;
	testLinkedStack_2 = testLinkedStack;

	std::cout << testLinkedStack_2.peek() << std::endl;

	std::cout << "testLinkedStack.getSize() : " << testLinkedStack.getSize() << std::endl;

	testLinkedStack.clean();
	std::cout << "testLinkedStack.getSize() : " << testLinkedStack.getSize() << std::endl;
	std::cout << testLinkedStack.getAllocatedSize() << std::endl;

	testLinkedStack.push(5);
	testLinkedStack.push(6);
	std::cout << "testLinkedStack.getSize() : " << testLinkedStack.getSize() << std::endl;
	std::cout << testLinkedStack.peek() << std::endl;


	return 0;
}

/*
The main entry point for the program.
*/
int main ( int argc, const char * argv[] )
{
    char input;
    LinkedStack s;

    while ( !cin.eof() )
    {
        cout << "Please enter a string." << endl;
        while ( cin.get ( input ) && input != ( char ) '\n' )
        {
            s.push ( input );
        }

        while ( !s.isEmpty() )
        {
            cout << s.pop();
        }

        cout << endl;
    }
}

int main()
{
    bool stay = true;

    // create one instance for each of the test classes

    cout << "\nInstanciate an object of LinkedStack\n";
    LinkedStack<string>* stackPtr = new LinkedStack<string>();

    cout << "\nProgram started, \n"
         << "    initiate the TEST DRIVER with a set of hard-wired data!\n"
         << "For example, \n"
         << "    you may use this set of tokens as a default test case: \n"
         << "    the, items, are, 123, 456, 789, and, abc";

    string choice; // user input for choices

    // initialize the LinkedStack class instances
    stackPtr->push("the");
    stackPtr->push("items");
    stackPtr->push("are");
    stackPtr->push("123");
    stackPtr->push("456");
    stackPtr->push("789");
    stackPtr->push("and");
    stackPtr->push("abc");
    cout << "\n   Use the P - peek command to view the stack.\n";

    // main menu while
    while(stay) {  // main menu while starts
        menu();
        stay = true;
        cin >> choice;
        cin.ignore();

        if(choice.size() == 1) {
            char ch = choice[0];
            vector<string> dump;
            string value;
            switch(ch) {  // main menu switch starts

            case 'd': // display stack
            case 'D':
                if(stackPtr->isEmpty()) {
                    cout << "\n		Stack is empty.\n";
                } else {
                    stackPtr->displayStack();
                }
                break;

            case 'e': // is stack empty?
            case 'E':
                if(stackPtr->isEmpty())
                {
                    cout << "\n		The list is empty\n";
                } else {
                    cout << "\n		There are items in the stack\n";
                }
                break;

            case 'i': // insert item
            case 'I':
                cout << "		insert item: ";
                cin >> value;
                stackPtr->push(value);
                break;

            case 'r': // remove item
            case 'R':
                if(stackPtr->isEmpty())
                {
                    cout << "\n		The list is empty\n";
                } else {
                    stackPtr->pop();
                    cout << "\n		Top item removed.\n";
                }
                break;

            case 'c': // clear stack
            case 'C':
                // to be completed by you;
                if(stackPtr->isEmpty()) {
                    cout << "\n		Stack already empty.\n";
                } else {
                    stackPtr->clear();
                }

                break;

            case 'p': // peek TOP value
            case 'P':
                cout << "\n		The top value is: " << stackPtr->peek() << endl;
                break;

            case 'q': // quit main menu
            case 'Q':
                stay = false;
                break;

            default:
//.........这里部分代码省略.........

bool checkExpression(const string& expression)
{
	LinkedStack<char> balancedStack;
	bool balancedSoFar = true;
	unsigned int i = 0;  // Used to keep track of position in expression
	int singleQuote = 0, doubleQuote = 0;  // Used to keep track of delimiters ' and "
	char ch;  // Holds character at position i in expression

	while ( balancedSoFar && (i < expression.length()) )
	{
		// Get first character in expression, then increment position
		ch = expression[i];
		i++;

		switch (ch)
		{	
			// Skip next character if escape character is found
			case '\\':
				i++;
				break;

			// Push an open token
			case '{':
			case '[':
			case '(':
				balancedStack.push(ch);
				break;
			case '\'':
			{
				singleQuote++;
				if (singleQuote % 2 == 0)
					balancedStack.pop();  // Pop matching delimiter
				else
					balancedStack.push(ch);
				break;
			} // end ' case
			case '"':
			{
				doubleQuote++;
				if (doubleQuote % 2 == 0)
					balancedStack.pop();  // Pop matching delimiter
				else
					balancedStack.push(ch);
				break;
			} // end " case
			
			// Close tokens
			case '}':
			case ']':
			case ')':
			{
				// Make sure stack is not empty and the close token matches the open
				if (!balancedStack.isEmpty() && 
					(  (balancedStack.peek() == '(') 
					|| (balancedStack.peek() == '{')
					|| (balancedStack.peek() == '[') ) )
					balancedStack.pop();  // Pop a matching closed token
				else                      // No matching closed token
					balancedSoFar = false;
				break;
			}
		} // end switch
	} // end while

	if ( !(balancedSoFar && balancedStack.isEmpty()) )
		balancedSoFar = false;

	return balancedSoFar;
} // end checkExpression