P2698 [USACO12MAR]Flowerpot S

https://www.luogu.com.cn/record/84127155

Luogu/P2698/P2698.cpp

@@ -0,0 +1,60 @@
+#include <iostream>
+#include <algorithm>
+#include <cmath>
+#include <limits>
+#include <set>
+#include <utility>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 1e5 + 5;
+
+int n, d, ans = std::numeric_limits<int>::max();
+std::pair<int, int> points[N];
+std::set<int> set;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> d;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> points[i].first >> points[i].second;
+    }
+
+    std::sort(points + 1, points + 1 + n, [](auto a, auto b) -> bool {
+        return a.second < b.second;
+    });
+
+    int lst = 1;
+    for (int i = 1; i <= n; i++) {
+        int pos = std::upper_bound(points + 1, points + 1 + n, std::make_pair(0, points[i].second - d), [](auto a, auto b) -> bool {
+                      return a.second < b.second;
+                  })
+                - points;
+
+        for (int j = lst; j < pos; j++) {
+            set.insert(points[j].first);
+        }
+
+        lst = pos;
+
+        auto it1 = set.lower_bound(points[i].first),
+             it2 = set.upper_bound(points[i].first);
+
+        if (it1 != set.begin()) {
+            ans = std::min(ans, std::abs(points[i].first - *--it1));
+        }
+
+        if (it2 != set.end()) {
+            ans = std::min(ans, std::abs(points[i].first - *it2));
+        }
+    }
+
+    cout << (ans == std::numeric_limits<int>::max() ? -1 : ans) << endl;
+
+    return 0;
+}