const LIMIT: usize = 100000;

fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();
    let items = (0..n).map(|_| {
            let mut temp = String::new();
            std::io::stdin().read_line(&mut temp).ok();
            let temp: Vec<usize> = temp.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
            (temp[0], temp[1])
        })
        .collect::<Vec<_>>();
    let mut v = String::new();
    std::io::stdin().read_line(&mut v).ok();
    let v: usize = v.trim().parse().unwrap();

    let mut dp = vec![vec![0usize; LIMIT+1]; n+1];
    for i in 0..n {
        let (v, w) = items[i];
        for j in 0..=LIMIT {
            dp[i+1][j] = dp[i+1][j].max(dp[i][j]);
            if j+w <= LIMIT {
                dp[i+1][j+w] = dp[i+1][j+w].max(dp[i][j] + v);
            }
        }
    }
    let mut min_flg = false;
    let mut max_flg = false;
    for i in 1..=LIMIT {
        if !min_flg && dp[n][i] == v {
            min_flg = true;
            println!("{}", i);
        }
        if i > 0 && dp[n][i-1] == v && dp[n][i] > v {
            max_flg = true;
            println!("{}", i-1);
        }
    }
    if !max_flg {
        println!("inf");
    }
}