#include <map>
#include <set>
#include <array>
#include <cmath>
#include <deque>
#include <bitset>
#include <random>
#include <string>
#include <vector>
#include <cassert>
#include <complex>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>

using namespace std;

const int MAXN = 4e5 + 100;
int add[MAXN * 4];
array<int, 2> tree[MAXN * 4];
int len[MAXN];

array<int, 2> operator*(const array<int, 2>& a, const array<int, 2>& b) {
  if (a[0] == b[0]) {
    return {a[0], a[1] + b[1]};
  }
  return min(a, b);
}

array<int, 2> operator+(const array<int, 2>& a, int x) {
  return {a[0] + x, a[1]};
}

void pull(int v) {
  tree[v] = tree[v * 2] * tree[v * 2 + 1] + add[v];
}

void build(int v, int vl, int vr) {
  add[v] = 0;
  if (vr - vl == 1) {
    tree[v] = {0, len[vl]};
    return;
  }
  int vm = (vl + vr) / 2;
  build(v * 2, vl, vm);
  build(v * 2 + 1, vm, vr);
  pull(v);
}

void update(int v, int vl, int vr, int l, int r, int val) {
  if (l >= vr || r <= vl) return;
  if (l <= vl && r >= vr) {
    add[v] += val;
    tree[v][0] += val;
    return;
  }
  int vm = (vl + vr) / 2;
  update(v * 2, vl, vm, l, r, val);
  update(v * 2 + 1, vm, vr, l, r, val);
  pull(v);
}

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

  cout << fixed << setprecision(20);

  int q, w;
  cin >> q >> w;
  set<array<int, 2>> has;
  vector<int> bord = {0, w};

  vector<array<int, 2>> ev(q);
  for (int i = 0; i < q; ++i) {
    int x, y;
    cin >> x >> y;
    ev[i] = {x, y};
    int l = max(0, x - y);
    int r = min(w, x + y);
    bord.push_back(l);
    bord.push_back(r);
  }

  sort(bord.begin(), bord.end());
  int k = unique(bord.begin(), bord.end()) - bord.begin();
  map<int, int> mp;
  for (int i = 0; i < k; ++i) {
    mp[bord[i]] = i;
  }
  for (int i = 0; i < k - 1; ++i) {
    len[i] = bord[i + 1] - bord[i];
  }
  build(1, 0, k - 1);
  for (int i = 0; i < q; ++i) {
    int x = ev[i][0], y = ev[i][1];
    int val = 1;
    if (has.count(ev[i])) {
      has.erase(ev[i]);
      val = -1;
    } else {
      has.insert(ev[i]);
    }
    int l = max(0, x - y);
    int r = min(w, x + y);
    l = mp[l]; r = mp[r];
    update(1, 0, k - 1, l, r, val);
    int len = w;
    if (tree[1][0] == 0) {
      len -= tree[1][1];
    }
    double ans = len;
    ans *= sqrtl(2);
    cout << ans << "\n";
  }



  
  return 0;
}