Submission #2296315

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Source Code Expand

use std::io::*;
use std::str::FromStr;
 
fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin
        .bytes()
        .map(|c| c.expect("failed to read char") as char)
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("failed to parse token")
}
 
fn main() {
    let n: usize = read();
    let h: usize = read();
    let mut aseq = vec![0; n];
    let mut bseq = vec![0; n];
    for i in 0..n {
        aseq[i] = read();
        bseq[i] = read();
    }
    let mut ans = 0;
    let mut sum = 0;
    aseq.sort();
    bseq.sort();
    aseq.reverse();
    bseq.reverse();
    for i in 0..n {
        if sum < h && aseq[0] < bseq[i] {
            ans += 1;
            sum += bseq[i];
        }
    }
    if sum < h {
        ans += (h - sum + aseq[0] - 1) / aseq[0];
    }
    println!("{}", ans);
}

Submission Info

Judge Result