Vector of structs initialization

Question

I want know how I can add values to my vector of structs using the push_back method

struct subject
{
  string name;
  int marks;
  int credits;
};

         


        

Answer 1

You cannot access elements of an empty vector by subscript.
Always check that the vector is not empty & the index is valid while using the [] operator on std::vector.
[] does not add elements if none exists, but it causes an Undefined Behavior if the index is invalid.

You should create a temporary object of your structure, fill it up and then add it to the vector, using vector::push_back()

subject subObj;
subObj.name = s1;
sub.push_back(subObj);