What is the easiest way to initialize a std::vector with hardcoded elements?

Question

I can create an array and initialize it like this:

int a[] = {10, 20, 30};

How do I create a std::vector and initialize it sim

Answer 1

A more recent duplicate question has this answer by Viktor Sehr. For me, it is compact, visually appealing (looks like you are 'shoving' the values in), doesn't require c++11 or a third party module, and avoids using an extra (written) variable. Below is how I am using it with a few changes. I may switch to extending the function of vector and/or va_arg in the future intead.

---

// Based on answer by "Viktor Sehr" on Stack Overflow
// https://stackoverflow.com/a/8907356
//
template 
class mkvec {
public:
    typedef mkvec my_type;
    my_type& operator<< (const T& val) {
        data_.push_back(val);
        return *this;
    }
    my_type& operator<< (const std::vector& inVector) {
        this->data_.reserve(this->data_.size() + inVector.size());
        this->data_.insert(this->data_.end(), inVector.begin(), inVector.end());
        return *this;
    }
    operator std::vector() const {
        return data_;
    }
private:
    std::vector data_;
};

std::vector    vec1;
std::vector    vec2;

vec1 = mkvec() << 5 << 8 << 19 << 79;  
// vec1 = (5,8,19,79)
vec2 = mkvec() << 1 << 2 << 3 << vec1 << 10 << 11 << 12;  
// vec2 = (1,2,3,5,8,19,79,10,11,12)