#include<bits/stdc++.h>
using namespace std;

const int N=200010;
const long double sqrt2=1.41421356237;
int n,m,root,tot;
set<pair<int,int> >s;
set<pair<int,int> >::iterator it;

struct SegmentTree{
    int ll[N*40],rr[N*40],sum[N*40],len[N*40];

    inline void change(int &p,int l,int r,int L,int R,int op)
    {
        
        if(!p)p=++tot;
        //cout<<"change "<<p<<" "<<l<<" "<<r<<" "<<L<<" "<<R<<" "<<op<<endl;
        if(L<=l&&r<=R)
        {
            sum[p]+=op;
            if(sum[p]>=1)len[p]=r-l+1;   
            else len[p]=len[ll[p]]+len[rr[p]];
            //cout<<"return "<<p<<" "<<sum[p]<<" "<<len[p]<<endl;;
            return;
        }
        int mid=l+r>>1;
        if(L<=mid)change(ll[p],l,mid,L,R,op);
        if(R>mid)change(rr[p],mid+1,r,L,R,op);
        if(sum[p]>=1)len[p]=r-l+1;   
        else len[p]=len[ll[p]]+len[rr[p]];
        //cout<<"return "<<p<<" "<<sum[p]<<" "<<len[p]<<endl;
    }

}t;

int main()
{
    scanf("%d%d",&n,&m);
    for(int i=1,x,y;i<=n;i++)
    {
        scanf("%d%d",&x,&y);
        int posl=max(0,x-y),posr=min(m,x+y);
        it=s.find(make_pair(x,y));
        if(it!=s.end())
        {
            s.erase(it);
            if(posr>posl)t.change(root,0,m,posl,posr-1,-1);
        }
        else 
        {
            s.insert(make_pair(x,y));
            if(posr>posl)t.change(root,0,m,posl,posr-1,1);
        }
        long double res=1.0*t.len[root];
        //cout<<t.len[root]<<endl;
        printf("%.12Lf\n",res*sqrt2);
    }
    return 0;
}