https://atcoder.jp/contests/abc343/tasks/abc343_d
選手ごとの得点のテーブルと、どの得点に何人いるかのマップを持っておきます。
// Diversity of Scores #![allow(non_snake_case)] //////////////////// library //////////////////// fn read<T: std::str::FromStr>() -> T { let mut line = String::new(); std::io::stdin().read_line(&mut line).ok(); line.trim().parse().ok().unwrap() } fn read_vec<T: std::str::FromStr>() -> Vec<T> { read::<String>().split_whitespace() .map(|e| e.parse().ok().unwrap()).collect() } //////////////////// Scores //////////////////// use std::collections::HashMap; struct Scores { table: Vec<i64>, counter: HashMap<i64, usize> } impl Scores { fn new(N: usize) -> Scores { let table: Vec<i64> = vec![0; N]; let mut counter = HashMap::new(); counter.insert(0, N); Scores { table, counter } } fn add(&mut self, A: usize, B: i64) { let prev = self.table[A]; self.table[A] += B; let e1 = self.counter.get_mut(&prev).unwrap(); *e1 -= 1; if *e1 == 0 { self.counter.remove(&prev); } let e2 = self.counter.entry(self.table[A]).or_insert(0); *e2 += 1 } fn diversity(&self) -> usize { self.counter.len() } } //////////////////// process //////////////////// fn read_input() -> (usize, usize) { let v = read_vec(); let (N, T) = (v[0], v[1]); (N, T) } fn read_query() -> (usize, i64) { let v = read_vec::<usize>(); let (A, B) = (v[0]-1, v[1] as i64); (A, B) } fn F(N: usize, T: usize) { let mut scores = Scores::new(N); for _ in 0..T { let (A, B) = read_query(); scores.add(A, B); println!("{}", scores.diversity()) } } fn main() { let (N, T) = read_input(); F(N, T) }