59 lines
1.3 KiB
Rust
59 lines
1.3 KiB
Rust
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use std::u64;
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fn is_increasing(levels: &Vec<u64>) -> bool {
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let mut current = 0;
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for item in levels {
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if *item < current {
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return false;
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} else {
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current = *item;
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}
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}
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return true;
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}
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fn is_decreasing(levels: &Vec<u64>) -> bool {
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let mut current = u64::MAX;
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for item in levels {
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if *item > current {
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return false;
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} else {
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current = *item;
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}
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}
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return true;
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}
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fn is_monotonous(levels: &Vec<u64>) -> bool {
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return is_increasing(levels) || is_decreasing(levels);
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}
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fn is_safe(levels: &Vec<u64>) -> bool {
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if !is_monotonous(levels) {
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return false;
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}
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for i in 0..(levels.len() - 1) {
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let j = i+1;
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let a = levels[i];
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let b = levels[j];
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let diff = (a as i64 - b as i64).abs() as u64;
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if diff < 1 || diff > 3 {
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return false;
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}
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}
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return true;
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}
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fn main() -> std::io::Result<()> {
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let mut count = 0;
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for line in std::io::stdin().lines() {
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let line = line.unwrap();
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let levels: Vec<u64> = line.split(" ").map(|x| x.parse::<u64>().unwrap()).collect();
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if is_safe(&levels) {
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count += 1;
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}
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}
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println!("{}", count);
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Ok(())
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}
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