A C++ Virtual Function Problem

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1 
class Generic : public Obj
{
  public:
    Generic() {  }
    virtual void set(const int pwm)
    {
       std::cout<< i am generic<<std::endl;
    }

this is base .

class Shoot : public Generic
{
  public:
    Shoot() {}
    virtual void set(const int left, const int right)
    {
        std::cout << "I am shoot set!" << left << " " << right << std::endl;
    }
};

this is son.

class SingleShoot : public Shoot
{
  public:
    SingleShoot () {}
    virtual void set(const int pwm) override
    {
        std::cout << "I am SngerShoot set!" << pwm << std::endl;
    }
};

this is grandson.

void opcontrol()
{
   std::shared_ptr<Generic> shoot =std::make_shared<SingleShoot>();
   shoot->set(127); // it's error,
}

Compiler Error Tips:
too few arguments to function call, expected 2, have 1; did you mean ‘Generic::set’?
‘Generic::set’ declared here
The simplest approach:
add virtual void set(int ){;} to class shoot

if i don’t add virtual void set(int pwm) =0 or virtual void set(int pwm) {;} in class Shootwhat should i do?

2

Did you try Stackoverflow? I saw some similar compilation error 2-3 days back there but couldn’t recall it.

Maybe give it a chance in the recent threads

3

My English is poor.I don’t know how to describe this problem.
There is no way to search on stack overflow.
Actually, it’s easy to solve, but the students asked this question. I don’t know how to answer it.

4

Edit: not a complete answer, but may help you on the right track with respect to the jargon used

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5