Add yukicoder/2798.rs yukicoder/2799.rs

yukicoder/2798.rs

@@ -0,0 +1,170 @@
+use std::io::Read;
+
+fn get_word() -> String {
+    let stdin = std::io::stdin();
+    let mut stdin=stdin.lock();
+    let mut u8b: [u8; 1] = [0];
+    loop {
+        let mut buf: Vec<u8> = Vec::with_capacity(16);
+        loop {
+            let res = stdin.read(&mut u8b);
+            if res.unwrap_or(0) == 0 || u8b[0] <= b' ' {
+                break;
+            } else {
+                buf.push(u8b[0]);
+            }
+        }
+        if buf.len() >= 1 {
+            let ret = String::from_utf8(buf).unwrap();
+            return ret;
+        }
+    }
+}
+
+fn get<T: std::str::FromStr>() -> T { get_word().parse().ok().unwrap() }
+
+// https://judge.yosupo.jp/submission/5155
+mod pollard_rho {
+    /// binary gcd
+    pub fn gcd(mut x: i64, mut y: i64) -> i64 {
+        if y == 0 { return x; }
+        if x == 0 { return y; }
+        let k = (x | y).trailing_zeros();
+        y >>= k;
+        x >>= x.trailing_zeros();
+        while y != 0 {
+            y >>= y.trailing_zeros();
+            if x > y { let t = x; x = y; y = t; }
+            y -= x;
+        }
+        x << k
+    }
+
+    fn add_mod(x: i64, y: i64, n: i64) -> i64 {
+        let z = x + y;
+        if z >= n { z - n } else { z }
+    }
+
+    fn mul_mod(x: i64, mut y: i64, n: i64) -> i64 {
+        assert!(x >= 0);
+        assert!(x < n);
+        let mut sum = 0;
+        let mut cur = x;
+        while y > 0 {
+            if (y & 1) == 1 { sum = add_mod(sum, cur, n); }
+            cur = add_mod(cur, cur, n);
+            y >>= 1;
+        }
+        sum
+    }
+
+    fn mod_pow(x: i64, mut e: i64, n: i64) -> i64 {
+        let mut prod = if n == 1 { 0 } else { 1 };
+        let mut cur = x % n;
+        while e > 0 {
+            if (e & 1) == 1 { prod = mul_mod(prod, cur, n); }
+            e >>= 1;
+            if e > 0 { cur = mul_mod(cur, cur, n); }
+        }
+        prod
+    }
+
+    pub fn is_prime(n: i64) -> bool {
+        if n <= 1 { return false; }
+        let small = [2, 3, 5, 7, 11, 13];
+        if small.iter().any(|&u| u == n) { return true; }
+        if small.iter().any(|&u| n % u == 0) { return false; }
+        let mut d = n - 1;
+        let e = d.trailing_zeros();
+        d >>= e;
+        // https://miller-rabin.appspot.com/
+        let a = [2, 325, 9375, 28178, 450775, 9780504, 1795265022];
+        a.iter().all(|&a| {
+            if a % n == 0 { return true; }
+            let mut x = mod_pow(a, d, n);
+            if x == 1 { return true; }
+            for _ in 0..e {
+                if x == n - 1 {
+                    return true;
+                }
+                x = mul_mod(x, x, n);
+                if x == 1 { return false; }
+            }
+            x == 1
+        })
+    }
+
+    fn pollard_rho(n: i64, c: &mut i64) -> i64 {
+        // An improvement with Brent's cycle detection algorithm is performed.
+        // https://maths-people.anu.edu.au/~brent/pub/pub051.html
+        if n % 2 == 0 { return 2; }
+        loop {
+            let mut x: i64; // tortoise
+            let mut y = 2; // hare
+            let mut d = 1;
+            let cc = *c;
+            let f = |i| add_mod(mul_mod(i, i, n), cc, n);
+            let mut r = 1;
+            // We don't perform the gcd-once-in-a-while optimization
+            // because the plain gcd-every-time algorithm appears to
+            // outperform, at least on judge.yosupo.jp :)
+            while d == 1 {
+                x = y;
+                for _ in 0..r {
+                    y = f(y);
+                    d = gcd((x - y).abs(), n);
+                    if d != 1 { break; }
+                }
+                r *= 2;
+            }
+            if d == n {
+                *c += 1;
+                continue;
+            }
+            return d;
+        }
+    }
+
+    /// Outputs (p, e) in p's ascending order.
+    pub fn factorize(x: i64) -> Vec<(i64, usize)> {
+        if x <= 1 { return vec![]; }
+        let mut hm = std::collections::HashMap::new();
+        let mut pool = vec![x];
+        let mut c = 1;
+        while let Some(u) = pool.pop() {
+            if is_prime(u) {
+                *hm.entry(u).or_insert(0) += 1;
+                continue;
+            }
+            let p = pollard_rho(u, &mut c);
+            pool.push(p);
+            pool.push(u / p);
+        }
+        let mut v: Vec<_> = hm.into_iter().collect();
+        v.sort();
+        v
+    }
+} // mod pollard_rho
+
+// Tags: partition-number
+fn main() {
+    let n: i64 = get();
+    let pe = pollard_rho::factorize(n);
+    const N: usize = 61;
+    let mut dp = vec![vec![0i64; N]; N];
+    dp[0] = vec![1; N];
+    for i in 1..N {
+        dp[i][1] = 1;
+        for j in 2..i + 1 {
+            dp[i][j] = dp[i][j - 1] + dp[i - j][j];
+        }
+        for j in i + 1..N {
+            dp[i][j] = dp[i][j - 1];
+        }
+    }
+    let mut ans = 1;
+    for (_, e) in pe {
+        ans *= dp[e][e];
+    }
+    println!("{}", ans);
+}

yukicoder/2799.rs

@@ -0,0 +1,64 @@
+// 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, $t)).collect::<Vec<_>>()
+    };
+    ($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error"));
+}
+
+// e.g., k = 3, 7 -> 1 6 -> 6 -> 3 3 -> 3 -> {}
+fn dfs(a: i64, k: i64) -> i64 {
+    if a <= k {
+        return a;
+    }
+    if a % 2 == 0 {
+        0
+    } else {
+        -1
+    }
+}
+
+fn main() {
+    input! {
+        n: usize, k: i64,
+        a: [i64; n],
+    }
+    let sum: i64 = a.iter().sum();
+    let mut prof = vec![];
+    for a in a {
+        prof.push(dfs(a, k));
+    }
+    prof.sort(); prof.reverse();
+    let mut ans = 0;
+    for i in 0..n {
+        if i % 2 == 0 {
+            ans += prof[i];
+        } else {
+            ans -= prof[i];
+        }
+    }
+    println!("{}", (sum + ans) / 2);
+}