C++11 Closures

#include <cstdio>
#include <functional>
#include <memory>
int main()
{
    auto fib = []() mutable{
        int j=0,k=1;
        std::shared_ptr<int> aa = std::shared_ptr<int>(new int(j));
        std::shared_ptr<int> bb = std::shared_ptr<int>(new int(k));
        int &a = *aa;
        int &b = *bb;
        a = 0;
        b = 1;
        return [=]() mutable {
            int t = b;
            b = a + b;
            a = t;
            return a;
        };
    };
    auto f = fib();
    printf("%d %d %d %d\n",f(),f(),f(),f()); // prints: "3 2 1 1" (Right to left function calling in C/C++)

}