szjy_6_树_012

阅读代码，程序输出是（ ）。

#include <iostream>
using namespace std;

struct Node {
int value;
Node* left = nullptr;
Node* right = nullptr;
};

int size(Node* root) {
if (root == nullptr) return 0;
return size(root->left) + size(root->right) + 1;
}

int main() {
Node a{8}, b{3}, c{10}, d{1}, e{6}, f{14};
a.left = &b;  a.right = &c;
b.left = &d;  b.right = &e;
c.right = &f;
cout << size(&a);
}

{{ select(1) }}

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