55 lines
828 B
Markdown
55 lines
828 B
Markdown
1.
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```rust
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fn main() {
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// don't modify the following two lines!
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let (x, y) = (1, 2);
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let s = sum(x, y);
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assert_eq!(s, 3);
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}
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fn sum(x: i32, y: i32) -> i32 {
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x + y
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}
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```
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2.
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```rust
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fn main() {
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print();
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}
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// replace i32 with another type
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fn print() -> () {
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println!("hello,world");
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}
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```
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3.
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```rust
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fn main() {
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never_return();
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}
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fn never_return() -> ! {
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// implement this function, don't modify fn signatures
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panic!("I return nothing!")
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}
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```
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```rust
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fn main() {
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never_return();
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}
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use std::thread;
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use std::time;
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fn never_return() -> ! {
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// implement this function, don't modify fn signatures
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loop {
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println!("I return nothing");
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// sleeping for 1 second to avoid exhausting the cpu resoucre
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thread::sleep(time::Duration::from_secs(1))
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}
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}
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``` |