szjy_6_树_048

给定的树是一棵二叉搜索树。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 minValue(Node* root) {
while (root->left != nullptr) root = root->left;
return root->value;
}

int main() {
Node a{15}, b{6}, c{23}, d{4}, e{7}, f{18}, g{71};
a.left = &b;  a.right = &c;
b.left = &d;  b.right = &e;
c.left = &f;  c.right = &g;
cout << minValue(&a);
}

{{ select(1) }}

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