LibreOJ: 2740

「JOISC 2016 Day 4」最差记者 2

Author: Macesuted

LibreOJ/2740.cpp

@@ -0,0 +1,93 @@
+/**
+ * @file 2740.cpp
+ * @author Macesuted ([email protected])
+ * @date 2023-02-08
+ *
+ * @copyright Copyright (c) 2023
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#ifndef LOCAL
+#define endl '\n'
+#endif
+
+bool mem1;
+
+#define maxn 400005
+
+typedef pair<int, int> pii;
+
+class SegmentTree {
+   private:
+    pii tree[maxn << 2];
+    int n;
+
+    pii merge(pii a, pii b) { return {a.first + b.first, min(a.second, a.first + b.second)}; }
+    void pushUp(int p) { return tree[p] = merge(tree[p << 1], tree[p << 1 | 1]), void(); }
+    void update(int p, int l, int r, int qp, int v) {
+        if (l == r) return tree[p] = {v, min(0, v)}, void();
+        int mid = (l + r) >> 1;
+        qp <= mid ? update(p << 1, l, mid, qp, v) : update(p << 1 | 1, mid + 1, r, qp, v);
+        return pushUp(p);
+    }
+    pii query(int p, int l, int r, int ql, int qr) {
+        if (ql <= l && r <= qr) return tree[p];
+        int mid = (l + r) >> 1;
+        if (qr <= mid) return query(p << 1, l, mid, ql, qr);
+        if (ql > mid) return query(p << 1 | 1, mid + 1, r, ql, qr);
+        return merge(query(p << 1, l, mid, ql, qr), query(p << 1 | 1, mid + 1, r, ql, qr));
+    }
+
+   public:
+    void resize(int _n) { return n = _n, void(); }
+    void update(int p, int v) { return update(1, 1, n, p, v); }
+    pii query(int l, int r) { return l > r ? pii{0, 0} : query(1, 1, n, l, r); }
+} ST;
+
+pii a[maxn];
+stack<int> S[maxn >> 1];
+
+void solve(void) {
+    int n;
+    cin >> n, ST.resize(2 * n);
+    for (int i = 1; i <= n; i++) cin >> a[i].first >> a[i].second;
+    for (int i = 1; i <= n; i++) cin >> a[n + i].first >> a[n + i].second, a[n + i].first *= -1;
+    sort(a + 1, a + 2 * n + 1, [](const pii& a, const pii& b) {
+        return a.second < b.second || (a.second == b.second && a.first > 0 && b.first < 0);
+    });
+    int ans = n;
+    for (int i = 1; i <= 2 * n; i++) {
+        ST.update(i, a[i].first / abs(a[i].first));
+        if (a[i].first > 0) {
+            S[a[i].first].push(i);
+            continue;
+        }
+        if (!S[-a[i].first].empty()) {
+            int p = S[-a[i].first].top();
+            if (ST.query(1, p - 1).first + ST.query(p + 1, i - 1).second >= 0)
+                ans--, S[-a[i].first].pop(), ST.update(p, 0), ST.update(i, 0);
+        }
+    }
+    cout << ans << endl;
+    return;
+}
+
+bool mem2;
+
+int main() {
+    ios::sync_with_stdio(false), cin.tie(nullptr);
+#ifdef LOCAL
+    cerr << "Memory Cost: " << abs(&mem1 - &mem2) / 1024. / 1024. << "MB" << endl;
+#endif
+
+    int _ = 1;
+    while (_--) solve();
+
+#ifdef LOCAL
+    cerr << "Time Cost: " << clock() * 1000. / CLOCKS_PER_SEC << "MS" << endl;
+#endif
+    return 0;
+}