// MagicDark
#include <bits/stdc++.h>
#define debug cerr << "\033[32m[" << __LINE__ << "]\033[0m "
#define SZ(x) ((int) x.size() - 1)
#define all(x) x.begin(), x.end()
#define ms(x, y) memset(x, y, sizeof x)
#define F(i, x, y) for (int i = (x); i <= (y); i++)
#define DF(i, x, y) for (int i = (x); i >= (y); i--)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
template <typename T> T& chkmax(T& x, T y) {return x = max(x, y);}
template <typename T> T& chkmin(T& x, T y) {return x = min(x, y);}
template <typename T> T& read(T &x) {
	x = 0; int f = 1; char c = getchar();
	for (; !isdigit(c); c = getchar()) if (c == '-') f = -f;
	for (; isdigit(c); c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48);
	return x *= f;
}
const int N = 2e5 + 10, M = N * 35;
const double sq2 = sqrt(2);
int q, w, rt, ls[M], rs[M], tot, len[M], tag[M];
map <int, set <int>> mp;
// struct Info {
// 	int lmx, rmx;
// 	double ans;
// } info[M];
int info[M];
// void pushup(int num) {
// 	info[num].lmx = max(info[ls[num]].lmx, info[rs[num]].lmx - len[ls[num]]);
// 	info[num].rmx = max(info[rs[num]].rmx, info[ls[num]].rmx - len[rs[num]]);
// 	if (info[ls[num]].rmx > info[rs[num]].lmx) {
// 		info[num] = info[ls[num]].ans + 
// 	} else {
// 		info[num] = info[ls[num]].ans + 
// 	}
// 	if (info[ls[num]])
// }
// double
void pushup(int num, int l, int r) {
	if (tag[num]) info[num] = r - l + 1;
	else info[num] = info[ls[num]] + info[rs[num]];
}
void ins(int& num, int l, int r, int L, int R, int x) {
	if (!num) num = ++tot, len[num] = r - l + 1;
	if (L <= l && r <= R) {
		tag[num] += x;
		pushup(num, l, r);
		// if (!tag[num])
		// if (mp[l].empty()) info[num].lmx = info[num].rmx = 0;
		return;
	}
	int mid = (l + r) >> 1;
	if (mid >= L) ins(ls[num], l, mid, L, R, x);
	if (mid < R) ins(rs[num], mid + 1, r, L, R, x);
	pushup(num, l, r);
}
signed main() {
	read(q), read(w);
	F(i, 1, q) {
		int x, y; read(x), read(y);
		// debug << max(0, x - y) << " " << min(w - 1, x + y - 1) << endl;
		if (mp[x].count(y)) mp[x].erase(y), ins(rt, 0, w - 1, max(0, x - y), min(w - 1, x + y - 1), - 1);
		else mp[x].insert(y), ins(rt, 0, w - 1, max(0, x - y), min(w - 1, x + y - 1), 1);
		cout << fixed << setprecision(6) << info[rt] * sq2 << '\n';
		// ins(1, 1, w, x);
	}
	return 0;
}
/* why?
*/