Rust Brain Teasers

Puzzle 14

Structure Sizing

structure_sizing/src/main.rs

use std::mem::size_of;

struct VeryImportantMessage {
    _message_type: u8,
    _destination: u16
}

fn main() {
    println!(
        "VeryImportantMessage occupies {} bytes.",
        size_of::<VeryImportantMessage>()
    );
}

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

The program will display the following output:

VeryImportantMessage occupies 4 bytes.

Discussion

_message_type and _destination are sized as you would expect, occupying 1 and 2 bytes ...