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| #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 5e4 + 50;
int n, r, l, cx, cy, fa[maxn], val[maxn];
bool vis[maxn];
int find(int x) { return x == fa[x] ? x : fa[x] = find(fa[x]); }
void join(int x, int y) {
int a = find(x), b = find(y);
if (a == b) return;
val[a] += val[b];
fa[b] = a;
}
struct node1 {
int x_, y_;
bool operator<(node1 &x) { return x_ < x.x_; }
} arr[maxn];
struct node2 {
int y_, id_;
node2(int y, int id) : y_(y), id_(id) {}
bool operator<(const node2 &x) const {
if (y_ != x.y_) return y_ < x.y_;
return id_ < x.id_;
}
};
set<node2> st;
int main() {
while (cin >> n >> r >> l) {
l /= 2;
st.clear(), memset(vis, 0, sizeof(vis));
for (int i = 1; i <= n; ++i) {
cin >> arr[i].x_ >> arr[i].y_;
fa[i] = i, val[i] = 1;
}
cin >> cx >> cy;
sort(arr + 1, arr + 1 + n);
int head = 1, tail = 1;
while (head <= tail && tail <= n) {
while (head <= tail && arr[tail].x_ - arr[head].x_ > l) {
st.erase(node2(arr[head].y_, head));
++head;
}
auto it = st.emplace(arr[tail].y_, tail).first;
if (it != st.begin() && it->y_ - prev(it)->y_ <= l) {
join(prev(it)->id_, it->id_);
}
if (next(it) != st.end() && next(it)->y_ - it->y_ <= l) {
join(it->id_, next(it)->id_);
}
++tail;
}
ll x, y, f, ans = 0;
for (int i = 1; i <= n; ++i) {
x = abs(arr[i].x_ - cx), y = abs(arr[i].y_ - cy);
if (x * x + y * y <= 1ll * r * r) {
f = find(i);
if (!vis[f]) vis[f] = 1, ans += val[f];
}
}
cout << ans << endl;
}
return 0;
}
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