Init

ACMOJ-2065.cpp

@@ -0,0 +1,78 @@
+#include <algorithm>
+#include <cstdio>
+#include <cstring>
+#include <vector>
+using namespace std;
+typedef long long LL;
+const int kMaxn = 2e5 + 10;
+struct DataType {
+  int r, y;
+  int uid, dfn, boundary;
+} val[kMaxn], tmp[kMaxn];
+vector<int> G[kMaxn];
+int n, dfn_cnt, res[kMaxn];
+void PreWork(int u, int fa) {
+  val[u].dfn = ++dfn_cnt;
+  for (int v : G[u]) {
+    if (v == fa) continue;
+    PreWork(v, u);
+  }
+  val[u].boundary = dfn_cnt;
+}
+class BSTType {
+  LL data[kMaxn];
+  int len = 0;
+
+ public:
+  void Init(int n) { len = n; }
+  void Modify(int p, int v) {
+    for (; p <= len; p += p & (-p)) data[p] += v;
+  }
+  LL Query(int p) {
+    LL res = 0;
+    for (; p > 0; p -= p & (-p)) res += data[p];
+    return res;
+  }
+} BST;
+void CDQ(int L, int R) {
+  if (L == R) return;
+  int M = (L + R) >> 1;
+  CDQ(L, M);
+  CDQ(M + 1, R);
+  sort(val + L, val + M + 1,
+       [](const DataType &A, const DataType &B) { return A.r < B.r; });
+  sort(val + M + 1, val + R + 1,
+       [](const DataType &A, const DataType &B) { return A.r < B.r; });
+  int pl = L, pr = M + 1;
+  while (pr <= R) {
+    while (pl <= M && val[pl].r <= val[pr].r) BST.Modify(val[pl++].dfn, 1);
+    res[val[pr].uid] += BST.Query(val[pr].boundary) - BST.Query(val[pr].dfn);
+    pr++;
+  }
+  for (int i = L; i < pl; i++) BST.Modify(val[i].dfn, -1);
+}
+int main() {
+#ifdef local
+  freopen("pro.in", "r", stdin);
+#endif
+  scanf("%d", &n);
+  for (int i = 1; i <= n - 1; i++) {
+    int u, v;
+    scanf("%d%d", &u, &v);
+    G[u].push_back(v);
+    G[v].push_back(u);
+  }
+  for (int i = 1; i <= n; i++) {
+    scanf("%d%d", &val[i].r, &val[i].y);
+    val[i].uid = i;
+  }
+  PreWork(1, 0);
+  BST.Init(n);
+  sort(val + 1, val + 1 + n, [](const DataType &A, const DataType &B) {
+    return A.y != B.y ? A.y < B.y : (A.r != B.r ? A.r < B.r : A.dfn > B.dfn);
+  });
+  CDQ(1, n);
+  for (int i = 1; i <= n; i++)
+    if (res[i] != 0) printf("%d\n", res[i]);
+  return 0;
+}