Rust Brain Teasers

Puzzle 17

How Long Is a Vector?

vec_size/src/main.rs

fn main() {
    let mut my_vec = Vec::with_capacity(1);
    my_vec.push("Hello");
    println!("{}", my_vec.capacity());
    my_vec.push("World");
    println!("{}", my_vec.capacity());
}

Guess the Output
	Try to guess what the output is before moving to the next page.

The program will display the following output:

1
4

Discussion

Vectors contain two things: a length indicating ...