数算！

dsa/ch5_binary_tree/luogu_P4715_matches.cpp

@@ -0,0 +1,62 @@
+#include <cmath>
+#include <functional>
+#include <iostream>
+
+class BinaryTree {
+public:
+    struct Node {
+        int value = -1;
+        Node *father = nullptr, *left = nullptr, *right = nullptr;
+        int depth = -1;
+    };
+
+    Node* root = new Node({.depth = 0});
+
+    void init_full_tree(int height, const std::function<bool(int, int)>& comp) {
+        int id = 0;
+        return init_full_tree(height, comp, 0, nullptr, id);
+    }
+
+protected:
+    void init_full_tree(int height, const std::function<bool(int, int)>& comp,
+                        int current_depth, Node* current_node, int& id) {
+        if (current_depth == 0) { current_node = root; }
+        if (current_depth == height) {
+            current_node->value = id++;
+            return;
+        }
+        current_node->left = new Node();
+        current_node->right = new Node();
+        init_full_tree(height, comp, current_depth + 1, current_node->left, id);
+        init_full_tree(height, comp, current_depth + 1, current_node->right, id);
+        if (comp(current_node->left->value, current_node->right->value)) {
+            current_node->value = current_node->right->value;
+        } else {
+            current_node->value = current_node->left->value;
+        }
+    }
+};
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    int n;
+    BinaryTree binary_tree;
+    std::vector<int> strengths;
+    std::cin >> n;
+    strengths.resize(static_cast<std::size_t>(std::pow(2, n)));
+    for (int& strength : strengths) { std::cin >> strength; }
+    binary_tree.init_full_tree(n,
+                               [strengths](int i, int j) {
+                                   return strengths[i] < strengths[j];
+                               });
+    // std::cout << binary_tree.root->value << std::endl;
+    int gold = binary_tree.root->value;
+    int silver = binary_tree.root->left->value == gold
+                     ? binary_tree.root->right->value
+                     : binary_tree.root->left->value;
+    std::cout << silver + 1 << std::endl;
+
+    return 0;
+}