29 lines
932 B
C++
29 lines
932 B
C++
#include <iostream>
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#include <memory>
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int main(){
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std::shared_ptr<int> age(new int(40));
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std::cout << "age is " << *age << std::endl;
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// you can never do this, which is assigning a smarter pointer to a raw pointer.
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// int * temp = age;
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{
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std::shared_ptr<int> temp = age;
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std::cout << "age is " << *temp << std::endl;
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std::cout << "the use count is : " << age.use_count() << std::endl;
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}
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std::cout << "the use count is : " << age.use_count() << std::endl;
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// give up my ownership, it decreases the reference count of the managed object by one.
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// if that shared pointer was the last owner (i.e., reference count becomes zero), the object is deleted.
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// the shared_ptr itself is now empty (i.e., it holds nullptr).
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age.reset();
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std::cout << "the use count is : " << age.use_count() << std::endl;
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// question: what happens if we print age here:
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// std::cout << "age is " << *age << std::endl;
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return 0;
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}
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