use std::cmp::*; use std::io::{Write, BufWriter}; // https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 macro_rules! input { ($($r:tt)*) => { let stdin = std::io::stdin(); let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock())); let mut next = move || -> String{ bytes.by_ref().map(|r|r.unwrap() as char) .skip_while(|c|c.is_whitespace()) .take_while(|c|!c.is_whitespace()) .collect() }; input_inner!{next, $($r)*} }; } macro_rules! input_inner { ($next:expr) => {}; ($next:expr,) => {}; ($next:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($next, $t); input_inner!{$next $($r)*} }; } macro_rules! read_value { ($next:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($next, $t)).collect::>() }; ($next:expr, [ $t:tt ]) => {{ let len = read_value!($next, usize); read_value!($next, [$t; len]) }}; ($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error")); } fn calc(mut a: Vec) -> bool { let n = a.len(); let mut de = vec![]; for k in 1..n - 1 { let ok = (a[k] > a[k + 1]) == (a[k] > a[k - 1]) && a[k] != a[k + 1] && a[k] != a[k - 1] && a[k - 1] != a[k + 1]; if !ok { de.push(k); } } if de.len() > 6 { return false; } let mut cand = vec![]; for &d in &de { for i in d - 1..d + 2 { cand.push(i); } } cand.sort(); cand.dedup(); let m = cand.len(); for i in 0..m { let x = cand[i]; for y in 0..n { let ok = de.iter().all(|&pos| min((pos as i64 - x as i64).abs(), (pos as i64 - y as i64).abs()) <= 1); if !ok { continue; } a.swap(x, y); let mut t = vec![]; for k in max(1, x) - 1..min(x + 2, n) { t.push(k); } for k in max(1, y) - 1..min(y + 2, n) { t.push(k); } t.sort_unstable(); t.dedup(); let ok = t.iter().all(|&k| { k == 0 || k == n - 1 || ( (a[k] > a[k + 1]) == (a[k] > a[k - 1]) && a[k] != a[k + 1] && a[k] != a[k - 1] && a[k - 1] != a[k + 1] ) }); a.swap(x, y); if ok { return true; } } } false } // https://yukicoder.me/problems/no/1369 (3) // 多数 (7 個以上) 門松列になっていない点がある場合は不可能。 // そうでない場合はそれらを全探索。-> 誤り。矛盾している点と矛盾していない点を交換することも // ありえる。 fn main() { let out = std::io::stdout(); let mut out = BufWriter::new(out.lock()); macro_rules! puts {($($format:tt)*) => (let _ = write!(out,$($format)*););} input!(a: [[usize]]); for a in a { puts!("{}\n", if calc(a) { "Yes" } else { "No" }); } }