from snapshot_array import SnapshotArray


def main(input_1, input_2):
    result = []
    snapshot_arr = SnapshotArray(input_2[0][0])
    result.append(None)
    for i in range(1, len(input_1)):
        if input_1[i] == "snap":
            res = snapshot_arr.snapshot()
            result.append(res)
        elif input_1[i] == "get":
            res = snapshot_arr.get_value(input_2[i][0], input_2[i][1])
            result.append(res)
        elif input_1[i] == "set":
            snapshot_arr.set_value(input_2[i][0], input_2[i][1])
            result.append(None)

    return result