LibreOJ: 2090

「ZJOI2016」旅行者

Author: Macesuted

LibreOJ/2090.cpp

@@ -0,0 +1,114 @@
+/**
+ * @file 2090.cpp
+ * @author Macesuted ([email protected])
+ * @date 2022-12-09
+ *
+ * @copyright Copyright (c) 2022
+ *
+ */
+
+#include <bits/stdc++.h>
+using namespace std;
+
+#ifndef LOCAL
+#define endl '\n'
+#endif
+
+bool mem1;
+
+#define maxn 20005
+#define maxq 100005
+
+typedef pair<int, int> pii;
+typedef tuple<int, int, int> tiii;
+
+int n, m;
+vector<vector<pii>> graph;
+priority_queue<pii, vector<pii>, greater<pii>> que;
+int dist[maxn], ans[maxq];
+bool vis[maxn];
+
+int _(int x, int y) { return (x - 1) * m + y; }
+pii $(int x) { return {(x - 1) / m + 1, (x - 1) % m + 1}; }
+
+void Dijkstra(int S, int xl, int xr, int yl, int yr) {
+    for (int x = xl; x <= xr; x++)
+        for (int y = yl; y <= yr; y++) dist[_(x, y)] = 1e9, vis[_(x, y)] = false;
+    que.emplace(dist[S] = 0, S);
+    while (!que.empty()) {
+        int p = que.top().second;
+        que.pop();
+        if (vis[p]) continue;
+        vis[p] = true;
+        for (auto i : graph[p])
+            if (xl <= $(i.first).first && $(i.first).first <= xr && yl <= $(i.first).second && $(i.first).second <= yr &&
+                dist[i.first] > dist[p] + i.second)
+                que.emplace(dist[i.first] = dist[p] + i.second, i.first);
+    }
+    return;
+}
+
+void solve(int xl, int xr, int yl, int yr, vector<tiii> ques) {
+    if (ques.empty()) return;
+    if (xl == xr && yl == yr) {
+        for (auto i : ques) ans[get<2>(i)] = 0;
+        return;
+    }
+    if (xr - xl > yr - yl) {
+        int xm = (xl + xr) >> 1;
+        for (int y = yl; y <= yr; y++) {
+            Dijkstra(_(xm, y), xl, xr, yl, yr);
+            for (auto i : ques) ans[get<2>(i)] = min(ans[get<2>(i)], dist[get<0>(i)] + dist[get<1>(i)]);
+        }
+        vector<tiii> sque[2];
+        for (auto i : ques)
+            if (($(get<0>(i)).first <= xm) == ($(get<1>(i)).first <= xm)) sque[$(get<0>(i)).first > xm].push_back(i);
+        solve(xl, xm, yl, yr, sque[0]), solve(xm + 1, xr, yl, yr, sque[1]);
+    } else {
+        int ym = (yl + yr) >> 1;
+        for (int x = xl; x <= xr; x++) {
+            Dijkstra(_(x, ym), xl, xr, yl, yr);
+            for (auto i : ques) ans[get<2>(i)] = min(ans[get<2>(i)], dist[get<0>(i)] + dist[get<1>(i)]);
+        }
+        vector<tiii> sque[2];
+        for (auto i : ques)
+            if (($(get<0>(i)).second <= ym) == ($(get<1>(i)).second <= ym)) sque[$(get<0>(i)).second > ym].push_back(i);
+        solve(xl, xr, yl, ym, sque[0]), solve(xl, xr, ym + 1, yr, sque[1]);
+    }
+    return;
+}
+
+void solve(void) {
+    cin >> n >> m, graph.resize(_(n, m) + 1);
+    for (int i = 1, v; i <= n; i++)
+        for (int j = 1; j < m; j++)
+            cin >> v, graph[_(i, j)].emplace_back(_(i, j + 1), v), graph[_(i, j + 1)].emplace_back(_(i, j), v);
+    for (int i = 1, v; i < n; i++)
+        for (int j = 1; j <= m; j++)
+            cin >> v, graph[_(i, j)].emplace_back(_(i + 1, j), v), graph[_(i + 1, j)].emplace_back(_(i, j), v);
+    int q;
+    cin >> q;
+    vector<tiii> ques;
+    for (int i = 1, sx, sy, tx, ty; i <= q; i++)
+        cin >> sx >> sy >> tx >> ty, ques.emplace_back(_(sx, sy), _(tx, ty), i), ans[i] = INT_MAX;
+    solve(1, n, 1, m, ques);
+    for (int i = 1; i <= q; i++) cout << ans[i] << 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;
+}