#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pdd pair<double, double>
#define F first
#define S second
#define all(x) x.begin(), x.end()
using namespace std;

struct coord
{
    vector<int> l;
    void insert(int x)
    {
        l.emplace_back(x);
    }
    void build()
    {
        sort(all(l));
        l.resize(unique(all(l)) - l.begin());
    }
    int index(int x)
    {
        return (int)(lower_bound(all(l), x) - l.begin());
    }
} xs;


int M;

struct segtree
{
    int weight[4 * 400005];
    int seg[4 * 400005], tag[4 * 400005];

    void init(vector<int> &l, int i = 1, int L = 1, int R = M)
    {
        if (L == R) 
            weight[i] = l[L] - l[L - 1];
        else 
        {
            int mid = (L + R) / 2;
            init(l, i << 1, L, mid);
            init(l, i << 1 | 1, mid + 1, R);
            weight[i] = weight[i << 1] + weight[i << 1 | 1];
        }
    }

    void modify(int mL, int mR, int v, int i = 1, int L = 1, int R = M)
    {
        if (mL <= L && R <= mR)
            tag[i] += v;
        else if (R < mL || mR < L)
            return;
        else 
        {
            int mid = (L + R) / 2;
            modify(mL, mR, v, i << 1, L, mid);
            modify(mL, mR, v, i << 1 | 1, mid + 1, R);
        }
        if (tag[i] == 0)
            seg[i] = seg[i << 1] + seg[i << 1 | 1];
        else 
            seg[i] = weight[i];
    }
} seg;

int N, Q, W;
int in[200005], idx[200005];
pii rg[200005];
map<pii, int> mp;

signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    cin >> Q >> W;
    for (int i = 1; i <= Q; i++)
    {
        int x, y;
        cin >> x >> y;
        if (mp.find(pii(x, y)) == mp.end())
        {   
            mp[pii(x, y)] = ++N;
            rg[N] = pii(max(0, x - y), min(W, x + y));
            xs.insert(rg[N].F), xs.insert(rg[N].S);
        }
        idx[i] = mp[pii(x, y)];
    }
    xs.build();
    M = (int)xs.l.size() - 1;
    seg.init(xs.l);
    for (int i = 1; i <= Q; i++)
    {
        int j = idx[i];
        in[j] ^= 1;
        seg.modify(xs.index(rg[j].F) + 1, xs.index(rg[j].S), (in[j] ? 1 : -1));
        cout << fixed << setprecision(10) << seg.seg[1] * sqrtl(2) << '\n';
    }

}