41 lines
862 B
Rust
41 lines
862 B
Rust
extern crate rand;
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trait Balanced {
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/// Returns true if the brackets are balanced
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fn is_balanced(&self) -> bool;
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}
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impl<'a> Balanced for str {
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fn is_balanced(&self) -> bool {
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let mut count = 0;
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for bracket in self.chars() {
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let change = match bracket {
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'[' => 1,
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']' => -1,
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_ => panic!("Strings should only contain brackets")
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};
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count += change;
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if count < 0 { return false; }
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}
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count == 0
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}
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}
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/// Generates random brackets
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fn generate_brackets(num: usize) -> String {
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use rand::random;
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(0..num).map(|_| if random() { '[' } else { ']' }).collect()
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}
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fn main() {
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for i in (0..10) {
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let brackets = generate_brackets(i);
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println!("{} {}", brackets, brackets.is_balanced())
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}
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}
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