P3960 [NOIP2017 提高组] 列队

https://www.luogu.com.cn/record/77127364

Luogu/P3960/P3960.cpp

@@ -0,0 +1,78 @@
+#include <iostream>
+#include <vector>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 3e5 + 5;
+
+struct node {
+    int l, r, d;
+
+    node()
+        : l(0), r(0), d(0) {}
+} tr[N << 4];
+
+int n, m, q, max, cnt, root[N];
+std::vector<long long> r[N];
+
+int query(int u, int l, int r, int x) {
+    if (l == r) return l;
+
+    int mid = l + r >> 1;
+    int c = mid - l + 1 - tr[tr[u].l].d;
+
+    if (x <= c) return query(tr[u].l, l, mid, x);
+    return query(tr[u].r, mid + 1, r, x - c);
+}
+
+void remove(int &u, int l, int r, int x) {
+    if (!u) u = ++cnt;
+    tr[u].d++;
+
+    if (l == r) return;
+
+    int mid = l + r >> 1;
+    if (x <= mid) remove(tr[u].l, l, mid, x);
+    else remove(tr[u].r, mid + 1, r, x);
+}
+
+long long row(int x, int y) {
+    int p = query(root[x], 1, max, y);
+    remove(root[x], 1, max, p);
+    return p < m ? 1ll * (x - 1) * m + p : r[x][p - m];
+}
+
+long long col(int y) {
+    int p = query(root[0], 1, max, y);
+    remove(root[0], 1, max, p);
+    return p <= n ? 1ll * p * m : r[0][p - n - 1];
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> m >> q;
+
+    max = std::max(n, m) + q;
+
+    for (int i = 1, x, y; i <= q; i++) {
+        cin >> x >> y;
+
+        long long p;
+        if (y == m) {  // 最后一列
+            p = col(x);
+            r[0].push_back(p);
+        } else {
+            p = row(x, y);
+            r[0].push_back(p);
+            r[x].push_back(col(x));
+        }
+
+        cout << p << endl;
+    }
+
+    return 0;
+}