#include <algorithm>
#include <vector>

// `data` is used as a plain fixed-size block of memory: we never call its
// own push_back, we manage size and capacity ourselves.
class Vector {
public:
    std::vector<int> data;
    int capacity;
    int size = 0;
    int copies = 0;

    explicit Vector(int capacity)
        : data(capacity), capacity(capacity) {}

    void pushBack(int value) {
        if (size == capacity) {
            std::vector<int> bigger(std::max(1, 2 * capacity));
            for (int i = 0; i < size; i++) {
                bigger[i] = data[i];
                copies++;
            }
            data = bigger;
            capacity = (int)bigger.size();
        }
        data[size] = value;
        size++;
    }

    int pushAll(const std::vector<int>& values) {
        for (int value : values) {
            pushBack(value);
        }
        return copies;
    }
};
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