// ki bood ke goft Ghatinga?

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<pii,int> ppiii;

// vectors and Sets:
#define vc vector
#define pb push_back
#define all(c) (c).begin(), (c).end()

// pairs
#define mp make_pair
#define fr first
#define sc second

// execution time check and Debug
#define StartEX clock_t startExeTime = clock();
#define EndEX clock_t endExeTime = clock();
#define ExTime cerr << "\nTotal Execution Time is: " << double(-double(startExeTime)+double(endExeTime)) / CLOCKS_PER_SEC;
#define debug(x) cerr << #x << " : " << x << '\n'
#define endl "\n"

// time optimization
#define Heh ios::sync_with_stdio(false);cin.tie(0);
#define Bah ios::sync_with_stdio(false);
#pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")

// useful functions
ll pw(ll a,ll b){
  ll ret = 1;
  ll mul = a;
  while(b > 0){
	if(b&1)
	  ret = (ret * mul);
	mul = (mul * mul);
	b >>= 1;
  }
  return ret;
}
ll pw(ll a,ll b,ll mod){
  ll ret = 1;
  ll mul = a;
  while(b > 0){
	if(b&1)
	  ret = (ret * mul) % mod;
	mul = (mul * mul) % mod;
	b >>= 1;
  }
  return ret;
}

ll to_int(string s){
  ll ret = 0;
  for(int i = 0 ; i < (int)s.size() ; i++) ret = 10 * ret + s[i] - '0';
  return ret;
}

bool deq(ld a , ld b){return (abs(a-b) < 0.000001);} // 10 ^ -6

ld f(ld a , ld b , ld p){
  ld ret = 0;
  ld l = min(max((ld)0 , b - a) , p);
  ret += a * l + l * l / 2;
  ret += b * (p - l);
  ret /= p;
  return ret;
}

struct node{
  int mn = 0 , cnt = 0;
  int lz = 0;
  int lf = -1 , rt = -1;
};

vc<node> sg;
node bse;
int sz;

int build(int ln){
  sg.pb(bse);
  sg[sz].cnt = ln;
  return sz++;
}
void push(int x , int v){
  sg[v].mn += x;
  sg[v].lz += x;
}
void shift(int v , int ln){
  if(sg[v].lf == -1) sg[v].lf = build((ln + 1) / 2);
  if(sg[v].rt == -1) sg[v].rt = build(ln / 2);
  push(sg[v].lz, sg[v].lf);
  push(sg[v].lz , sg[v].rt);
  sg[v].lz = 0;
}
void upd(int v , int tl , int tr , int l , int r , int x){
  if(l > tr or r < tl) return;
  if(l <= tl and r >= tr){
    push(x , v);
    return;
  }
  shift(v , (tr - tl + 1));
  int mid = (tl + tr) / 2;
  upd(sg[v].lf , tl , mid , l , r , x) , upd(sg[v].rt , mid+1 , tr , l , r , x);
  if(sg[sg[v].lf].mn < sg[sg[v].rt].mn){
    sg[v].mn = sg[sg[v].lf].mn;
    sg[v].cnt = sg[sg[v].lf].cnt;
  }
  else if(sg[sg[v].rt].mn < sg[sg[v].lf].mn){
    sg[v].mn = sg[sg[v].rt].mn;
    sg[v].cnt = sg[sg[v].rt].cnt;
  }
  else{
    sg[v].mn = sg[sg[v].rt].mn;
    sg[v].cnt = sg[sg[v].lf].cnt + sg[sg[v].rt].cnt;
  }
}

void print(int v , int tl , int tr){
  cout << v << " " << tl << " " << tr << " " << sg[v].mn << " " << sg[v].cnt << endl;
  if(tl == tr) return;
  
  if(sg[v].lf != -1){
    shift(v , tr - tl + 1);
    int mid = (tl + tr) / 2;
    print(sg[v].lf , tl , mid) , print(sg[v].rt , mid+1 , tr);
  }
  
}

int main()
{
  Heh;
  int q , w;
  cin >> q >> w;
  build(w);
  map<pii,int> is;
  while(q--){
    int x , y;
    cin >> x >> y;
    int l = max(0 , x - y) , r = min(w , x + y) - 1;

    if(is[{x,y}] == 1){
      upd(0 , 0 , w-1 , l , r , -1);
      is[{x,y}] = 0;
    }
    else{
      upd(0 , 0 , w-1 , l , r , +1);
      is[{x,y}] = 1;
    }

    // print(0 , 0 , w-1);
    
    int c = w - sg[0].cnt;
    if(sg[0].mn != 0) c = w;
    cout << fixed << setprecision(10) << sqrt((ld)2) * c << endl;
  }
}

// ki seda kard Patinga?