#include <deque> #include <iostream> using namespace std; int main() { int n, k; cin >> n >> k; int last = 1, pos = 0; deque<int> dq; int dir = 0; auto push = [&](int x) -> void { if (dir == 0) { dq.push_back(x); } else { dq.push_front(x); } }; auto pop = [&]...