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25 lines
572 B
25 lines
572 B
3 years ago
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fn first_word(s: &String) -> usize {
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let bytes = s.as_bytes();
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for (i, &item) in bytes.iter().enumerate() {
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if item == b' ' {
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return i;
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}
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}
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s.len()
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}
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// ANCHOR: here
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fn main() {
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let mut s = String::from("hello world");
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let word = first_word(&s); // word will get the value 5
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s.clear(); // this empties the String, making it equal to ""
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// word still has the value 5 here, but there's no more string that
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// we could meaningfully use the value 5 with. word is now totally invalid!
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}
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// ANCHOR_END: here
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