AC atcoder/abc338/e

Cargo.toml

@@ -886,3 +886,11 @@ path = "atcoder/abc337/e/main.rs"
 [[bin]]
 name = "atcoder-abc338-d-main"
 path = "atcoder/abc338/d/main.rs"
+
+[[bin]]
+name = "atcoder-abc338-e-main"
+path = "atcoder/abc338/e/main.rs"
+
+[[bin]]
+name = "atcoder-abc338-e-main-v2"
+path = "atcoder/abc338/e/main_v2.rs"

atcoder/abc338/e/main.rs

@@ -0,0 +1,96 @@
+// WA
+
+// https://atcoder.jp/contests/abc338/tasks/abc338_e
+
+// This configuration is also possible...
+//   5 -- 0
+//  4      1
+//   \    /
+//   3    2
+
+fn main() {
+    // ~ 10^5
+    let n: usize = read_vec()[0];
+    let mut ls: Vec<[usize; 2]> = (0..n).map(|_| read_array()).collect();
+
+    // TODO: only possible configuraiton?
+    //   5 -- 0
+    //  4 ---- 1
+    //   3 -- 2
+
+    // normalize into such configuration
+    let k = ls.iter().find_map(|&[x, y]| {
+        if x.abs_diff(y) == 1 {
+            Some(x.max(y))
+        } else {
+            None
+        }
+    });
+    if k.is_none() {
+        println!("Yes");
+        return;
+    }
+    let k = k.unwrap();
+    for i in 0..n {
+        ls[i][0] = (ls[i][0] + 2 * n - k) % (2 * n);
+        ls[i][1] = (ls[i][1] + 2 * n - k) % (2 * n);
+        ls[i].sort();
+    }
+    ls.sort();
+
+    // verify configuration
+    let ok = (0..n).all(|i| ls[i] == [i, 2 * n - i - 1]);
+    println!("{}", if ok { "No" } else { "Yes" });
+}
+
+/*
+python misc/run.py atcoder/abc338/e/main.rs
+
+%%%% begin
+3
+1 3
+4 2
+5 6
+%%%%
+Yes
+%%%% end
+
+%%%% begin
+3
+6 1
+4 3
+2 5
+%%%%
+No
+%%%% end
+
+%%%% begin
+4
+2 4
+3 7
+8 6
+5 1
+%%%%
+Yes
+%%%% end
+*/
+
+//
+// utils
+//
+
+#[allow(dead_code)]
+fn read_vec<T: std::str::FromStr>() -> Vec<T> {
+    let mut line = String::new();
+    std::io::stdin().read_line(&mut line).unwrap();
+    line.split_whitespace()
+        .map(|s| s.parse().ok().unwrap())
+        .collect()
+}
+
+#[allow(dead_code)]
+fn read_array<T: std::str::FromStr, const LEN: usize>() -> [T; LEN] {
+    #[allow(unused_imports)]
+    use std::convert::TryInto;
+    read_vec::<T>().try_into().ok().unwrap()
+}

atcoder/abc338/e/main_v2.rs

@@ -0,0 +1,89 @@
+// AC
+
+// https://atcoder.jp/contests/abc338/tasks/abc338_e
+
+fn main() {
+    // ~ 10^5
+    let n: usize = read_vec()[0];
+    let mut ls: Vec<[usize; 2]> = (0..n).map(|_| read_array()).collect();
+
+    // check edge in-out makes stack such as
+    // ++++++++++ +++++++ +++++
+    //  ++++++     +++     +++
+    //    +++               +
+
+    // position, id, in/out
+    let mut events: Vec<(usize, usize, bool)> = vec![];
+    for i in 0..n {
+        ls[i].sort();
+        events.push((ls[i][0], i, true));
+        events.push((ls[i][1], i, false));
+    }
+    events.sort();
+
+    let mut stack: Vec<usize> = vec![];
+    for &(_, i, is_in) in &events {
+        if is_in {
+            stack.push(i);
+        } else {
+            let j = stack.pop();
+            if j != Some(i) {
+                println!("Yes");
+                return;
+            }
+        }
+    }
+    println!("No");
+}
+
+/*
+python misc/run.py atcoder/abc338/e/main_v2.rs
+
+%%%% begin
+3
+1 3
+4 2
+5 6
+%%%%
+Yes
+%%%% end
+
+%%%% begin
+3
+6 1
+4 3
+2 5
+%%%%
+No
+%%%% end
+
+%%%% begin
+4
+2 4
+3 7
+8 6
+5 1
+%%%%
+Yes
+%%%% end
+*/
+
+//
+// utils
+//
+
+#[allow(dead_code)]
+fn read_vec<T: std::str::FromStr>() -> Vec<T> {
+    let mut line = String::new();
+    std::io::stdin().read_line(&mut line).unwrap();
+    line.split_whitespace()
+        .map(|s| s.parse().ok().unwrap())
+        .collect()
+}
+
+#[allow(dead_code)]
+fn read_array<T: std::str::FromStr, const LEN: usize>() -> [T; LEN] {
+    #[allow(unused_imports)]
+    use std::convert::TryInto;
+    read_vec::<T>().try_into().ok().unwrap()
+}