Fizzbuzz Cheat Sheet
This is a syntax cheat sheet to be used with the Fizzbuzz exercise.
Variables
#![allow(unused)]
fn main() {
let thing = 42; // an immutable variable
let mut thing = 43; // a mutable variable
}
Functions
// a function with one argument, no return.
fn number_crunch(input: u32) {
// function body
}
// a function with two arguments and a return type.
fn division_machine(dividend: f32, divisor: f32) -> f32 {
// function body
let quotient = dividend / divisor;
// return line does not have a semi-colon!
quotient
}
fn main() {
let cookies = 1000.0_f32;
let cookie_monsters = 1.0_f32;
// calling a function
let number = division_machine(cookies, cookie_monsters);
}
for loops and ranges
#![allow(unused)]
fn main() {
// for loop with end-exclusive range
for i in 0..10 {
// do this
}
// for loop with end-inclusive range
for j in 0..=10 {
// do that
}
}
if - statements
#![allow(unused)]
fn main() {
let number = 4;
if number == 4 {
println!("This happens");
} else if number == 5 {
println!("Something else happens");
} else {
println!("Or this happens");
}
// condition can be anything that evaluates to a bool
}
Operators (Selection)
| Operator | Example | Explanation |
|---|---|---|
!= | expr != expr | Nonequality comparison |
== | expr == expr | Equality comparison |
&& | expr && expr | Short-circuiting logical AND |
|| | expr || expr | Short-circuiting logical OR |
% | expr % expr | Arithmetic remainder |
/ | expr / expr | Arithmetic division |