Often, we start with a vector that’s either empty or a certain length. As we read or compute data we want, we can grow the vector as needed.
.push_back()
To add a new element to the “back”, or end of the vector, we can use the .push_back()
function.
For example, suppose we have a vector called dna
with three letter codes of nucleotides:
std::vector<std::string> dna = {"ATG", "ACG"};
It would look like:
We can add elements using .push_back()
:
dna.push_back("GTG"); dna.push_back("CTG");
So now dna
would look like:
.pop_back()
You can also remove elements from the “back” of the vector using .pop_back()
.
dna.pop_back();
Notice how nothing goes inside the parentheses.
The vector would now look like:
because CTG
is removed!
Note: If you have programmed in other languages, be aware that .pop_back()
has no return value in C++.
Instructions
Inside the code editor, we have a std::string
vector.
Add these four strings using .push_back()
:
"kylo"
"rey"
"luke"
"finn"