Add examples for judge-update-202004-{A..D}

qryxip · qryxip · commit 2c0ad1f7a5d6 · 2020-05-19T00:20:09.000+09:00
diff --git a/examples/judge-update-202004-a.rs b/examples/judge-update-202004-a.rs
@@ -0,0 +1,26 @@
+// https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_a
+//
+// 以下のクレートを使用。
+// - `num`
+//     - `num-traits`
+// - `proconio`
+
+use proconio::input;
+
+fn main() {
+    // `proconio::input!`で入力を読む。
+    //
+    // https://docs.rs/proconio/0.3/proconio/macro.input.html
+    input! {
+        s: i32,
+        l: i32,
+        r: i32,
+    }
+
+    // `num_traits::clamp`で解く。
+    // 定義は`clamp(s, l, r) == if s < l { l } else if s > r { r } else { s }`。
+    // `PartialOrd`までしか要求しないので`f64`に対しても使える。
+    //
+    // https://docs.rs/num-traits/0.2/num_traits/fn.clamp.html
+    println!("{}", num::clamp(s, l, r));
+}
diff --git a/examples/judge-update-202004-b.rs b/examples/judge-update-202004-b.rs
@@ -0,0 +1,29 @@
+// https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_b
+//
+// 以下のクレートを使用。
+// - `itertools`
+// - `proconio`
+
+use itertools::Itertools as _;
+use proconio::{fastout, input};
+
+// `#[proconio::fastout]`で標準出力を高速化する。
+//
+// https://docs.rs/proconio-derive/0.1/proconio_derive/attr.fastout.html
+#[fastout]
+fn main() {
+    // `proconio::input!`で入力を読む。
+    //
+    // https://docs.rs/proconio/0.3/proconio/macro.input.html
+    input! {
+        xcs: [(u32, char)],
+    }
+
+    // `itertools::Itertools::sorted_by_key`で昇順かつ`R`, `B`の順に並び換えた(色, 書かれた整数)のイテレータを得る。
+    // その実装は単純に`Vec<_>`にしたあと`.sort_by_key(..)`して`.into_iter()`しているだけ。
+    //
+    // https://docs.rs/itertools/0.9/itertools/trait.Itertools.html#method.sorted_by_key
+    for (x, _) in xcs.into_iter().sorted_by_key(|&(x, c)| (c == 'B', x)) {
+        println!("{}", x);
+    }
+}
diff --git a/examples/judge-update-202004-c.rs b/examples/judge-update-202004-c.rs
@@ -0,0 +1,60 @@
+// https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_c
+//
+// 以下のクレートを使用。
+// - `itertools`
+// - `itertools-num`
+// - `proconio`
+
+use itertools::{iproduct, Itertools as _};
+use itertools_num::ItertoolsNum as _;
+use proconio::input;
+use std::iter;
+
+fn main() {
+    // `proconio::input!`で入力を読む。
+    //
+    // https://docs.rs/proconio/0.3/proconio/macro.input.html
+    input! {
+        r#as: [usize; 3],
+    }
+
+    // `itertools::Itertools::permutations`で順列を列挙。
+    // 一つ一つ`Vec<_>`を作るので気になるなら`superslice`/`permutohedron`の`next_permutation`か`permutohedron`の`heap_recursive`を。
+    //
+    // https://docs.rs/itertools/0.9/itertools/trait.Itertools.html#method.permutations
+    // https://docs.rs/superslice/1/superslice/trait.Ext.html#tymethod.next_permutation
+    // https://docs.rs/permutohedron/0.2/permutohedron/trait.LexicalPermutation.html#tymethod.next_permutation
+    // https://docs.rs/permutohedron/0.2/permutohedron/fn.heap_recursive.html
+    let ans = (0..r#as.iter().sum())
+        .permutations(r#as.iter().sum())
+        .filter(|perm| {
+            // `itertools_num::ItertoolsNum::cumsum`で累積和のイテレータが得られる。
+            // そしてその"windows"を`itertools::Itertools::tuple_windows`でイテレータからそのまま得る。
+            // 今回場合`perm`を3分割するだけだが..
+            //
+            // https://docs.rs/itertools-num/0.1/itertools_num/trait.ItertoolsNum.html#method.cumsum
+            // https://docs.rs/itertools/0.9/itertools/trait.Itertools.html#method.tuple_combinations
+            let x = iter::once(&0)
+                .chain(&r#as)
+                .cumsum()
+                .tuple_windows()
+                .map(|(c1, c2)| &perm[c1..c2])
+                .collect::<Vec<_>>();
+
+            // `for i in 0..3 { for j in 0..3 { .. } }`の代わりに`itertools::iproduct!`を使う。
+            //
+            // https://docs.rs/itertools/0.9/itertools/macro.iproduct.html
+
+            let horz = iproduct!(0..3, 0..3)
+                .filter(|&(i, j)| i > 0 && j < r#as[i])
+                .all(|(i, j)| x[i][j] > x[i - 1][j]);
+
+            let vert = iproduct!(0..3, 0..3)
+                .filter(|&(i, j)| j > 0 && j < r#as[i])
+                .all(|(i, j)| x[i][j] > x[i][j - 1]);
+
+            horz && vert
+        })
+        .count();
+    println!("{}", ans);
+}
diff --git a/examples/judge-update-202004-d.rs b/examples/judge-update-202004-d.rs
@@ -0,0 +1,48 @@
+// https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_d
+//
+// 以下のクレートを使用。
+// - `proconio`
+// - `superslice`
+
+use proconio::{fastout, input};
+use superslice::Ext as _;
+
+// `#[proconio::fastout]`で標準出力を高速化する。
+//
+// https://docs.rs/proconio-derive/0.1/proconio_derive/attr.fastout.html
+#[fastout]
+fn main() {
+    // `proconio::input!`で入力を読む。
+    //
+    // https://docs.rs/proconio/0.3/proconio/macro.input.html
+    input! {
+        n: usize,
+        q: usize,
+        r#as: [usize; n],
+        ss: [usize; q],
+    }
+
+    // `num_integer::gcd`でGCDを得る。
+    //
+    // https://docs.rs/num-integer/0.1/num_integer/fn.gcd.html
+    let gcds = r#as
+        .into_iter()
+        .scan(0, |gcd, a| {
+            *gcd = num::integer::gcd(*gcd, a);
+            Some(*gcd)
+        })
+        .collect::<Vec<_>>();
+
+    for s in ss {
+        // "j"を`superslice::Ext::lower_bound_by`で二分探索することで求める。
+        //
+        // https://docs.rs/superslice/1/superslice/trait.Ext.html#tymethod.lower_bound_by
+        let j = gcds.lower_bound_by(|&gcd| 1usize.cmp(&num::integer::gcd(gcd, s)));
+        let ans = if j < n {
+            j + 1
+        } else {
+            num::integer::gcd(s, gcds[n - 1])
+        };
+        println!("{}", ans);
+    }
+}
diff --git a/test-examples.toml b/test-examples.toml
@@ -290,6 +290,34 @@ url = "https://atcoder.jp/contests/atc002/tasks/atc002_b"
 matching = "Words"
 meta = { using = ["num", "proconio"] }
 
+[examples.judge-update-202004-a]
+type = "Normal"
+name = "Judge System Update Test Contest 202004: A - Walking Takahashi"
+url = "https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_a"
+matching = "Words"
+meta = { using = ["num", "proconio"] }
+
+[examples.judge-update-202004-b]
+type = "Normal"
+name = "Judge System Update Test Contest 202004: B - Picking Balls"
+url = "https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_b"
+matching = "Words"
+meta = { using = ["itertools", "proconio"] }
+
+[examples.judge-update-202004-c]
+type = "Normal"
+name = "Judge System Update Test Contest 202004: C - Numbering Blocks"
+url = "https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_c"
+matching = "Words"
+meta = { using = ["itertools", "itertools-num", "proconio"] }
+
+[examples.judge-update-202004-d]
+type = "Normal"
+name = "Judge System Update Test Contest 202004: D - Calculating GCD"
+url = "https://atcoder.jp/contests/judge-update-202004/tasks/judge_update_202004_d"
+matching = "Words"
+meta = { using = ["proconio", "superslice"] }
+
 [examples.panasonic2020-d]
 type = "Normal"
 name = "Panasonic Programming Contest 2020: D - String Equivalence"
