#include <bits/stdc++.h>
//#define int long long
#define fi first
#define se second 
#define pb push_back
#define ott(i, l, r) for (register int i = (l); i <= (r); i ++)
#define tto(i, l, r) for (register int i = (r); i >= (l); i --)
using namespace std;
typedef long long ll;
typedef long double ld;
int read () {
	int x = 0; bool f = false; char c = getchar ();
	while (!isdigit (c)) f |= (c == '-'), c = getchar ();
	while (isdigit (c)) x = (x << 3) + (x << 1) + (c ^ 48), c = getchar ();
	return f ? -x : x;
}
const int N = 2e5 + 110, mod = 1e9 + 7;
int n, m, q, w, res;
pair <int, int> p[N];
map <int, map <int, bool> > del;
int main () {
	q = read (), w = read ();
	ott (j, 1, q) {
		register int x = read (), y = read ();
		bool ok = true, ko = false; ott (i, 1, n) {
			if (p[i].fi <= x && p[i].fi + p[i].se >= x + y) ok = false;
			if (p[i].fi >= x && p[i].fi - p[i].se <= x - y) ok = false;
			if (p[i].fi == x && p[i].se == y && del[x][y]) ko = true;
		}
		del[x][y] ^= 1;
		if (ko) {
			m = 0; 
			ott (i, 1, n) if (p[i].fi ^ x || p[i].se ^ y) p[++ m] = p[i];
			n = m;
		}
		else if (ok) {
			m = 0; ott (i, 1, n) {
				if (p[i].fi < x && p[i].fi - p[i].se <= x - y) p[++ m] = p[i];
				if (p[i].fi > x && p[i].fi + p[i].se >= x + y) {
					if (p[m].fi < x) p[++ m] = {x, y};
					p[++ m] = p[i];
				}
			}
			if (p[m].fi < x) p[++ m] = {x, y};
			n = m;
		}
		if (n) res = min (p[1].fi, p[1].se) + min (w - p[n].fi, p[n].se) + p[n].fi - p[1].fi;
		else res = 0;
		printf ("%.6lf\n", 1.0 * res * pow (2, 0.5));
		// printf ("i = %d\n", j); ott (i, 1, n) printf ("[%d, %d]\n", p[i].fi, p[i].se);
	}

    return 0;
}