#1516. 【2022 正睿 NOIP 十连测 Day 1】区间 (range)

https://sjzezoj.com/submission/60321

S2OJ/1516/1516.cpp

@@ -0,0 +1,69 @@
+#include <iostream>
+#include <algorithm>
+#include <functional>
+#include <queue>
+#include <utility>
+#include <vector>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 2505;
+
+int n, k, l[N], r[N], w[N];
+long long sum, f[N << 1];
+std::vector<int> nums;
+std::vector<std::pair<int, int>> g[N << 1];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> k;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> l[i] >> r[i] >> w[i];
+
+        nums.emplace_back(l[i]);
+        nums.emplace_back(r[i]);
+        sum += w[i];
+    }
+
+    std::sort(nums.begin(), nums.end());
+    nums.erase(std::unique(nums.begin(), nums.end()), nums.end());
+
+    for (int i = 1; i <= n; i++) {
+        l[i] = std::lower_bound(nums.begin(), nums.end(), l[i]) - nums.begin() + 1;
+        r[i] = std::lower_bound(nums.begin(), nums.end(), r[i]) - nums.begin() + 1;
+
+        g[l[i]].emplace_back(r[i], w[i]);
+    }
+
+    for (int i = 1; i <= nums.size(); i++) {
+        std::priority_queue<int, std::vector<int>, std::greater<>> q;
+        long long res = 0;
+
+        for (int j = i; j; j--) {
+            for (auto e : g[j]) {
+                if (e.first <= i) {
+                    if (q.size() < k) {
+                        q.emplace(e.second);
+                        res += e.second;
+                    } else if (q.top() < e.second) {
+                        res -= q.top();
+                        q.pop();
+                        q.emplace(e.second);
+                        res += e.second;
+                    }
+                }
+            }
+
+            f[i] = std::max(f[i], f[j - 1] + res);
+        }
+    }
+
+    cout << sum - f[nums.size()] << endl;
+
+    return 0;
+}