#include <bits/stdc++.h>
using namespace std;
const int mod = 998244353;
inline int read() {
    int x = 0, f = 1;
    char c = getchar();
    while (c < '0' || c > '9')
        f = (c == '-') ? -1 : 1, c = getchar();
    while (c >= '0' && c <= '9')
        x = x * 10 + c - 48, c = getchar();
    return f * x;
}
struct node {
    int v, min, lazy;
} a[1000010];
void pushup(int k) {
    if (a[k << 1].min == a[k << 1 | 1].min)
        a[k].min = a[k << 1].min, a[k].v = a[k << 1 | 1].v + a[k << 1].v;
    if (a[k << 1].min < a[k << 1 | 1].min)
        a[k].min = a[k << 1].min, a[k].v = a[k << 1].v;
    if (a[k << 1].min > a[k << 1 | 1].min)
        a[k].min = a[k << 1 | 1].min, a[k].v = a[k << 1 | 1].v;
}
void build(int k, int l, int r) {
    if (l == r) {
        a[k].lazy = 0, a[k].v = 1, a[k].min = 0;
        return;
    }
    int mid = (l + r) >> 1;
    build(k << 1, l, mid);
    build(k << 1 | 1, mid + 1, r);
    pushup(k);
}
void pushdown(int k) {
    if (!a[k].lazy)
        return;
    a[k << 1].min += a[k].lazy;
    a[k << 1 | 1].min += a[k].lazy;
    a[k << 1].lazy += a[k].lazy;
    a[k << 1 | 1].lazy += a[k].lazy;
    a[k].lazy = 0;
}
void update(int k, int l, int r, int begin, int end, int v) {
    if (l > end || r < begin)
        return;
    if (l >= begin && r <= end) {
        a[k].min += v;
        a[k].lazy += v;
        return;
    }
    pushdown(k);
    int mid = (l + r) >> 1;
    update(k << 1, l, mid, begin, end, v);
    update(k << 1 | 1, mid + 1, r, begin, end, v);
    pushup(k);
}
int find(int k, int l, int r, int begin, int end) {
    if (l > end || r < begin)
        return 0;
    if (l >= begin && r <= end) {
        if (a[k].min == 0)
            return a[k].v;
        else
            return 0;
    }
    pushdown(k);
    int mid = (l + r) >> 1;
    if (end <= mid)
        return find(k << 1, l, mid, begin, end);
    else if (begin > mid)
        return find(k << 1 | 1, mid + 1, r, begin, end);
    else
        return find(k << 1, l, mid, begin, mid) +
               find(k << 1 | 1, mid + 1, r, mid + 1, end);
}
map<pair<int, int>, int> f;
signed main() {
    int q = read(), w = read();
    build(1, 1, w + 1);
    while (q--) {
        int x = read(), y = read();
        int l = max(x - y, 0) + 1, r = min(w, x + y) + 1;
        f[{x, y}]++;
        int p = f[{x, y}];
        if (p % 2 == 1)
            update(1, 1, w + 1, l, r, 1);
        else
            update(1, 1, w + 1, l, r, -1);
        int P = find(1, 1, w + 1, 1, w + 1);
        P = w + 1 - P;
        if (P == 0)
            P = 1;
        printf("%.7lf\n", sqrt(2) * (P - 1));
    }
}