P2345 [USACO04OPEN] MooFest G

https://www.luogu.com.cn/record/77636791

Luogu/P2345/P2345.cpp

@@ -0,0 +1,32 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 5e4 + 5;
+
+int n;
+long long ans;
+std::pair<int, int> p[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> p[i].first >> p[i].second;
+    }
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j < i; j++) {
+            ans += 1ll * std::max(p[i].first, p[j].first) * std::abs(p[i].second - p[j].second);
+        }
+    }
+
+    cout << ans << endl;
+
+    return 0;
+}