#include <bits/stdc++.h>

using namespace std;

using ll = long long;

class scan_line {
  public:
    vector<ll> val, len, ls, rs;
    ll n, idx;

    scan_line(ll t) {
      n = t;
      idx = 1;
      val.resize(100 * n);
      len.resize(100 * n);
      ls.resize(100 * n);
      rs.resize(100 * n);
    }

    void modify(ll l, ll r, ll t, ll p, ll tl, ll tr) {
      if (r < tl || l > tr || r < l) return;
      ll mid = (tl + tr) >> 1;
      if (l <= tl && r >= tr) val[p] += t;
      else {
        if (!ls[p]) ls[p] = ++idx;
        if (!rs[p]) rs[p] = ++idx;
        modify(l, r, t, ls[p], tl, mid);
        modify(l, r, t, rs[p], mid + 1, tr);
      }
      if (val[p]) len[p] = tr - tl + 1;
      else if (!ls[p]) len[p] = 0;
      else len[p] = len[ls[p]] + len[rs[p]];
    }

    void modify(ll l, ll r, ll t) {
      if (r >= l) modify(l, r, t, 1, 0ll, 1000000000ll);
    }

    ll slen() {
      return len[1];
    }
};

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);

	int q, w;
	cin >> q >> w;
	set<pair<int, int>> s;
	
	scan_line sc(q);
	
	while (q--) {
		int x, y;
		cin >> x >> y;
		
		const int l = max(0, x - y), r = min(w, x + y);
		
		if (s.find({x, y}) == s.end()) {
			s.insert({x, y});
			sc.modify(l + 1, r, 1);
		} else {
			s.erase({x, y});
			sc.modify(l + 1, r, -1);
		}
		
		cout << setprecision(15) << __builtin_sqrtl(2) * (double)sc.slen() << '\n';
	}

  return 0;
}