P2471 [SCOI2007]降雨量 [50' Code]

R52594509 #Unaccepted

Luogu/problem/P2471/P2471.cpp

@@ -0,0 +1,98 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+struct node {
+    int l, r, max;
+
+    node() {
+        l = r = max = 0;
+    }
+    node(int _l, int _r) {
+        l = _l;
+        r = _r;
+        max = 0;
+    }
+} tr[50005 << 2];
+
+int n, m, x, y, a[50005];
+map<int, int> m1;
+
+void pushup(int u) {
+    tr[u].max = max(tr[u << 1].max, tr[u << 1 | 1].max);
+}
+
+void build(int u, int l, int r) {
+    tr[u] = node(l, r);
+    if (l == r) {
+        tr[u].max = a[l];
+        return;
+    }
+    int mid = l + r >> 1;
+    build(u << 1, l, mid);
+    build(u << 1 | 1, mid + 1, r);
+    pushup(u);
+}
+
+int query(int u, int l, int r) {
+    if (l <= tr[u].l && tr[u].r <= r) {
+        return tr[u].max;
+    }
+    int mid = tr[u].l + tr[u].r >> 1;
+    int s = 0;
+    if (l <= mid) s = max(s, query(u << 1, l, r));
+    if (r > mid) s = max(s, query(u << 1 | 1, l, r));
+    return s;
+}
+
+int main() {
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> x >> y;
+        m1[x] = i;
+        a[i] = y;
+    }
+    build(1, 1, n);
+    cin >> m;
+    for (int i = 0; i < m; i++) {
+        cin >> y >> x;
+        if (y >= x) {
+            cout << "false" << endl;
+            continue;
+        }
+        bool exist_x = m1.count(x);
+        bool exist_y = m1.count(y);
+        auto it_x = m1.lower_bound(x);
+        auto it_y = m1.lower_bound(y);
+        if (!exist_x) {
+            if (!exist_y) {
+                cout << "maybe" << endl;
+            } else {
+                if (query(1, m1[y] + 1, (it_x == m1.end() ? (--m1.end())->second : it_x->second - 1)) < a[m1[x]]) {
+                    cout << "maybe" << endl;
+                } else {
+                    cout << "false" << endl;
+                }
+            }
+        } else {
+            if (exist_y) {
+                if (a[m1[y]] < a[m1[x]]) {
+                    cout << "false" << endl;
+                } else if (query(1, m1[y] + 1, m1[x] - 1) >= a[m1[x]]) {
+                    cout << "false" << endl;
+                } else if (x - y == m1[x] - m1[y]) {
+                    cout << "true" << endl;
+                } else {
+                    cout << "maybe" << endl;
+                }
+            } else {
+                if (it_y == m1.end() || query(1, it_y->second, m1[x] - 1) >= a[m1[x]]) {
+                    cout << "false" << endl;
+                } else {
+                    cout << "maybe" << endl;
+                }
+            }
+        }
+    }
+    return 0;
+}