class Solution {
    public String stringShift(String s, int[][] shift) {
        Deque<Character> chars = new ArrayDeque<>();
        for (char c : s.toCharArray()) {
            chars.push(c);
        }

        for (int[] ar : shift) {
            for (int i = 0; i < ar[1]; i++) {
                if (ar[0] == 1) {
                    Character c = chars.pollFirst();
                    chars.addLast(c);
                } else {
                    Character c = chars.pollLast();
                    chars.addFirst(c);

                }
            }
        }
        StringBuilder sb = new StringBuilder();
        Character last = chars.pollLast();
        while (last != null) {
            sb.append(last);
            last = chars.pollLast();
        }
        return sb.toString();
    }
}