I got following code that intends to extract value from map of pointers, modified pointed object and insert it back. But inserting does not work.

struct A{
    std::string name;
    mutable uint64_t s;
    mutable uint64_t b;
    bool operator<(const A& a)const {
        return name < a.name;
    }
};

struct classcomp
{

    bool operator ()(const A* lhs, const A* rhs) const {
        return A->s > A->s;
    }
};
...
    std::set<struct A*, classcomp> largestS;

...
    auto myS = largestS.extract(largestS.begin());
    myS.value()->s -=20;
    largestS.insert(std::move(myS));

What am I doing wrong. I use Visual Studio 2022 and C++ 17.