Added example for Practice2-K

Author: TonalidadeHidrica

examples/practice2_k_range_affine_range_sum.rs

@@ -0,0 +1,67 @@
+use ac_library_rs::{LazySegtree, MapMonoid, ModInt998244353, Monoid};
+use std::io::Read;
+
+type Mint = ModInt998244353;
+struct Sum;
+impl Monoid for Sum {
+    type S = (Mint, usize);
+
+    fn identity() -> Self::S {
+        (0.into(), 0)
+    }
+
+    fn binary_operation((a, n): Self::S, (b, m): Self::S) -> Self::S {
+        (a + b, n + m)
+    }
+}
+struct Affine;
+impl MapMonoid for Affine {
+    type M = Sum;
+    type F = (Mint, Mint);
+
+    fn identity_map() -> Self::F {
+        (1.into(), 0.into())
+    }
+
+    fn mapping((a, b): Self::F, (x, n): <Self::M as Monoid>::S) -> <Self::M as Monoid>::S {
+        (a * x + b * Mint::new(n), n)
+    }
+
+    // a(cx + d) + b = (ac)x + (ad+b)
+    fn composition((a, b): Self::F, (c, d): Self::F) -> Self::F {
+        (a * c, a * d + b)
+    }
+}
+
+#[allow(clippy::many_single_char_names)]
+fn main() {
+    let mut buf = String::new();
+    std::io::stdin().read_to_string(&mut buf).unwrap();
+    let mut input = buf.split_whitespace();
+
+    let n = input.next().unwrap().parse().unwrap();
+    let q = input.next().unwrap().parse().unwrap();
+    let mut segtree: LazySegtree<Affine> = input
+        .by_ref()
+        .take(n)
+        .map(|s| (s.parse().unwrap(), 1))
+        .collect::<Vec<_>>()
+        .into();
+    for _ in 0..q {
+        match input.next().unwrap().parse().unwrap() {
+            0 => {
+                let l = input.next().unwrap().parse().unwrap();
+                let r = input.next().unwrap().parse().unwrap();
+                let b = input.next().unwrap().parse().unwrap();
+                let c = input.next().unwrap().parse().unwrap();
+                segtree.apply_range(l, r, (b, c));
+            }
+            1 => {
+                let l = input.next().unwrap().parse().unwrap();
+                let r = input.next().unwrap().parse().unwrap();
+                println!("{}", segtree.prod(l, r).0);
+            }
+            _ => {}
+        }
+    }
+}