java中Stack类

List<Integer> weekList = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7));

        weekList.removeAll(Arrays.asList(2,3,5));

        List<Stack<Integer>> group = new ArrayList<>();
        //1,4,6,7
        loopA:
        for (Integer weekday : weekList) {
            for (Stack<Integer> stack : group) {
                if (stack.lastElement().equals(weekday - 1)) {
                    stack.push(weekday);//6
                    continue loopA;
                }
            }
            Stack<Integer> newStack = new Stack<>();
            newStack.push(weekday);//1 3 5
            group.add(newStack);//1 3 5
        }