41 lines
1.3 KiB
Rust
41 lines
1.3 KiB
Rust
// options1.rs
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//
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// Execute `rustlings hint options1` or use the `hint` watch subcommand for a
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// hint.
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// This function returns how much icecream there is left in the fridge.
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// If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
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// all, so there'll be no more left :(
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fn maybe_icecream(time_of_day: u16) -> Option<u16> {
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// We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a
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// value of 0 The Option output should gracefully handle cases where
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// time_of_day > 23.
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// TODO: Complete the function body - remember to return an Option!
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if time_of_day < 22 { Some(5) }
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else if time_of_day >= 22 && time_of_day < 25 { Some(0) }
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else { None }
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn check_icecream() {
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assert_eq!(maybe_icecream(9), Some(5));
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assert_eq!(maybe_icecream(10), Some(5));
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assert_eq!(maybe_icecream(23), Some(0));
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assert_eq!(maybe_icecream(22), Some(0));
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assert_eq!(maybe_icecream(25), None);
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}
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#[test]
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fn raw_value() {
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// TODO: Fix this test. How do you get at the value contained in the
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// Option?
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let icecreams = maybe_icecream(12).expect("No icecream");
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assert_eq!(icecreams, 5u16);
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}
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}
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