fn main() {
	// // input_interactive
	// input_interactive!{
	// 	_n: i64,
	// }
	
	let mut ans = 1_500_000_000 as i64;
	loop {
		// output
		println!("{}", ans);

		// judge
		input_interactive!{
			x: i64,
		}

		if x == -1 {
			return;
		}
		else if x == 1 {
			println!("{}", ans);
		}
		else {
			ans /= 2;
		}
	}
}

// const MOD17: usize = 1000000007;
// const MOD93: usize = 998244353;
// const INF: usize = 1 << 60;
// let dx = vec![!0, 0, 1, 0]; // 上左下右
// let dy = vec![0, !0, 0, 1]; // 上左下右
// let d = vec!{(!0, 0), (0, !0), (1, 0), (0, 1)}; // 上左下右

#[allow(unused)]
use proconio::{input_interactive, marker::Chars, marker::Usize1};

#[allow(unused)]
use std::{
	mem::swap,
	cmp::min, cmp::max,
	cmp::Reverse,
	collections::HashSet, collections::BTreeSet,
	collections::HashMap, collections::BTreeMap,
	collections::BinaryHeap,
	collections::VecDeque,
	iter::FromIterator,
};