c++ programming

Write a template function that takes as a parameter a vector of objects of some unknown class and two objects obj1 and obj2 of the same class. Modify the input vector to replace every instance of obj1 in the vector with obj2. If no instances of obj1 are found, add a new element at the end of the vector containing obj2. The function is not a member of any class. (Recall that you can access vectors like arrays, but they have useful methods like size and push_back. Vector declarations look like this: vector varName