Interview problem: Implement unique pointer 

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template <typename T>
class UniquePtr {
public:
    explicit UniquePtr(T *ptr=nullptr): ptr_(ptr){}

    ~UniquePtr(){
        delete ptr_;
    }

    UniquePtr(const UniquePtr &other) = delete;

    UniquePtr& operator=(const UniquePtr &other) = delete;

    UniquePtr(UniquePtr &&other) noexcept: ptr_(other.ptr_) {
        other.ptr_ = nullptr;
    }

    UniquePtr& operator=(UniquePtr &&other) noexcept {
        other.swap(*this);
        return *this;
    }

    T& operator*() const {
        return *ptr_;
    }

    T* operator->() const {
        return ptr_;
    }

    explicit operator bool() const {
        return ptr_;
    }

    void swap(UniquePtr &other) noexcept {
        std::swap(ptr_, other.ptr_);
    }

private:
    T *ptr_;
};
Location: 美国加利福尼亚州帕罗奥图

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