private boolean pushProduction(int topStack, int tokenInput)
	{
		int p = PARSER_TABLE[topStack-FIRST_NON_TERMINAL][tokenInput-1];
		if (p >= 0)
		{
			int[] production = PRODUCTIONS[p];
			//empilha a produ��o em ordem reversa
			for (int i=production.length-1; i>=0; i--)
			{
				stack.push(new Integer(production[i]));
			}
			return true;
		} else {
			return false;
		}
	}