Size and capacity

size

size_type size() const noexcept;

Returns: the number of elements in the vector.

empty

bool empty() const noexcept;

Returns: true if the vector is empty; false, otherwise.

max_size

size_type max_size() const noexcept;

Returns: the maximum number of elements that the vector can hold.

capacity

size_type capacity() const noexcept;

Returns: the maximum number of elements that the vector can hold without allocating more memory.