use std::io::Write; use std::collections::*; type Map = BTreeMap; type Set = BTreeSet; type Deque = VecDeque; fn run() { input! { n: usize, q: usize, a: [u32; n], ask: [(u8, usize1, u32); q], } let mut set = Set::new(); let mut a = a; for (i, a) in a.iter().enumerate() { if *a > 1 { set.insert(i); } } let out = std::io::stdout(); let mut out = std::io::BufWriter::new(out.lock()); for (op, x, y) in ask { if op == 1 { set.remove(&x); a[x] = y; if y > 1 { set.insert(x); } } else { let y = y as usize; let win = if let Some(&p) = set.range(x..y).next_back() { (y - p - 1) % 2 == 0 } else { (y - x) % 2 == 1 }; println!("{}", if win {"F"} else {"S"}); } } } fn main() { run(); } // ---------- begin input macro ---------- // reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 #[macro_export] macro_rules! input { (source = $s:expr, $($r:tt)*) => { let mut iter = $s.split_whitespace(); input_inner!{iter, $($r)*} }; ($($r:tt)*) => { let s = { use std::io::Read; let mut s = String::new(); std::io::stdin().read_to_string(&mut s).unwrap(); s }; let mut iter = s.split_whitespace(); input_inner!{iter, $($r)*} }; } #[macro_export] macro_rules! input_inner { ($iter:expr) => {}; ($iter:expr, ) => {}; ($iter:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($iter, $t); input_inner!{$iter $($r)*} }; } #[macro_export] macro_rules! read_value { ($iter:expr, ( $($t:tt),* )) => { ( $(read_value!($iter, $t)),* ) }; ($iter:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($iter, $t)).collect::>() }; ($iter:expr, chars) => { read_value!($iter, String).chars().collect::>() }; ($iter:expr, bytes) => { read_value!($iter, String).bytes().collect::>() }; ($iter:expr, usize1) => { read_value!($iter, usize) - 1 }; ($iter:expr, $t:ty) => { $iter.next().unwrap().parse::<$t>().expect("Parse error") }; } // ---------- end input macro ----------