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#![feature(iter_map_windows)]
use std::io;
fn main() {
let input: Vec<Vec<i64>> = io::stdin()
.lines()
.map(|line| {
line.unwrap()
.split_whitespace()
.map(str::parse::<i64>)
.collect()
})
.collect::<Result<Vec<_>, _>>()
.unwrap();
let silver: usize = input.iter().filter(|&xs| all_safe(xs)).count();
let gold: usize = input.iter().filter(|&xs| drop_safe(xs)).count();
println!("silver: {silver}");
println!("gold: {gold}");
}
fn all_safe(xs: &Vec<i64>) -> bool {
let mut diffs = xs.iter().map_windows(|&[x, y]| y - x).peekable();
let dir = diffs.peek().unwrap_or(&1).signum();
diffs.all(|d| (1..=3).contains(&d.abs()) && d.signum() == dir)
}
fn drop_safe(xs: &Vec<i64>) -> bool {
(0..xs.len())
.map(|idx| xs.split_at(idx))
.any(|(left, right)| all_safe(&[left, &right[1..]].concat()))
}
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