fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: isize = n.trim().parse().unwrap();
    let mut lower = 1isize;
    let mut upper = n-1;
    println!("? {}", lower);
    let mut sl = String::new();
    std::io::stdin().read_line(&mut sl).ok();
    let sl: isize = sl.trim().parse().unwrap();
    let sl = 2*sl - lower;
    println!("? {}", upper);
    let mut sr = String::new();
    std::io::stdin().read_line(&mut sr).ok();
    let sr: isize = sr.trim().parse().unwrap();
    let sr = 2*sr - upper;
    if sl == sr {
        println!("! {} {}", 2, n-1);
        return;
    }
    while upper > lower {
        let middle = (upper + lower) / 2;
        println!("? {}", middle);
        let mut temp = String::new();
        std::io::stdin().read_line(&mut temp).ok();
        let temp: isize = temp.trim().parse().unwrap();
        let temp = temp*2 - middle;
        if temp == 0 {
            upper = middle;
            lower = middle;
            break;
        }
        if temp * sl < 0 {
            upper = middle;
        } else {
            lower = middle+1;
        }
    }
    if lower >= n/2 {
        println!("! {} {}", 1, lower);
    } else {
        println!("! {} {}", lower+1, n);
    }
}