use proconio::input;

fn main() {
    input! {
        n: usize,
        mut ab: [(u32, u32); n],
    }

    ab.sort_unstable_by_key(|v| v.0);

    let mut max = 1;
    for &(a, b) in &ab {
        if a > max {
            break;
        }

        max = max.max(b);
    }

    println!("{max}");
}