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#[derive(Debug)]
enum UpState {
Alabama,
Alaska,
}
enum Coin {
Penny,
Nickel,
Dime,
Quarter(UpState),
}
fn main() {
let state = UpState::Alaska;
let coin = Coin::Quarter(state);
println!("the quater is {}",value_in_cents(coin));
println!("x = {:?}", plus_one(None));
}
fn value_in_cents(coin: Coin) -> u8 {
match coin {
Coin::Penny => 1,
Coin::Nickel => 5,
Coin::Dime => 10,
Coin::Quarter(state) => {
println!("state quarter from {:?}",state);
25
}
}
}
fn plus_one(x: Option<i32>) -> Option<i32> {
match x {
None => None,
Some(i) => Some(i+1),
}
}
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