Deque (Double Ended Queue)

NOT THREAD SAFE

C++ vs Python vs Rust

C++ Rust Python
Declaration deque<int> dq let mut dq:VecDeque<i32> = VecDeque::new(); self.dq = deque()
push at end dq.push_back(x) dq.push_back(x) self.dq.append(x)
Front, Back element dq.front(), dq.back() 

// Front
if let Some(front) = dq.front() {
    println!("{}", front);
}
dq.back()
self.dq[0],self.dq[-1]
Pop front, back dq.pop_front(), dq.pop_back() dq.pop_front(), dq.pop_back() self.dq.pop(), self.dq.popleft()
Check empty !dq.empty() !dq.empty() bool(self.dq) != False
size dq.size() dq.len() len(self.dq)