FSM using member function pointers

#include <iostream>

using namespace std;

class Fsm
{
public:
    Fsm() : state(&Fsm::initState) {}

    void run(int i)
    {
        (this->*state)(i);
    }

private:
    void initState(int i)
    {
        if(i>=0) state=&Fsm::statePositive;
        else state=&Fsm::stateNegative;
    }

    void statePositive(int i)
    {
        cout<<"Last number was positive"<<endl;
        if(i>=0) state=&Fsm::statePositive;
        else state=&Fsm::stateNegative;
    }

    void stateNegative(int i)
    {
        cout<<"Last number was negative"<<endl;
        if(i>=0) state=&Fsm::statePositive;
        else state=&Fsm::stateNegative;
    }

    void (Fsm::* state)(int);
};

int main()
{
    Fsm fsm1;
    Fsm fsm2;

    fsm1.run(10);
    fsm2.run(-2);
    fsm1.run(0);
    fsm2.run(0);
}