std::queue

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Example

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main: () = {
    q: std::queue<int> = ();
 
    q.push(0); // back pushes 0
    q.push(1); // q = 0 1
    q.push(2); // q = 0 1 2
    q.push(3); // q = 0 1 2 3
 
    assert(q.front() == 0);
    assert(q.back() == 3);
    assert(q.size() == 4);
 
    q.pop(); // removes the front element, 0
    assert(q.size() == 3);
 
    // Print and remove all elements. Note that std::queue does not
    // support begin()/end(), so a range-for-loop cannot be used.
    std::cout << "q: ";
    while !q.empty() next q.pop() {
        std::cout << "(q.front())$ ";
    }
    std::cout << '\n';
    assert(q.size() == 0);
}

Output

q: 1 2 3