c++ vector size

The std::vector is a dynamic array in C++ that can grow or shrink in size. It provides a convenient way to store and manipulate collections of elements. The size() function is a member function of the std::vector class that returns the number of elements in the vector.

Here are the steps to get the size of a std::vector in C++:

1. Declare and initialize a std::vector object:

cpp std::vector<int> myVector = {1, 2, 3, 4, 5};

In this example, we declare a std::vector called myVector and initialize it with five integers.

1. Use the size() function to get the size of the vector:

cpp int vectorSize = myVector.size();

The size() function returns the number of elements in the vector, which is then assigned to the variable vectorSize.

1. Print the size of the vector:

cpp std::cout << "The size of the vector is: " << vectorSize << std::endl;

This line of code prints the size of the vector to the console.

The output of the above code will be:

The size of the vector is: 5

This indicates that the vector myVector contains 5 elements.