C++ closure capture variable

Question

In the Cow() function. I'm trying to capture the variable weight to the closure. But it doesn't work correctly. Variable weight is not captured to the closure. When I was trying to run getWeight() function. It returned an uninitialized value. Also setWeight() does not work.

#include <iostream>

struct Mammal {
  std::function<void()> speak;
  std::function<int()> getWeight;
  std::function<void(int)> setWeight;
};

Mammal *Cow() {
    int weight = 100;

    auto *m = new Mammal();
    m->speak = []() { puts("momo~~ momo~~"); };
    m->getWeight = [&]() { return weight; };;
    m->setWeight = [&](int w) { weight = w; };

    return m;
}

int main() {
    Mammal *c = Cow();
    std::cout << "Cow Weight: " << c->getWeight() << '\n';

    c->setWeight(200);
    std::cout << "Cow New Weight: " << c->getWeight() << '\n';
}