学步园

#include <iostream><br /> using namespace std;<br /> struct Node {<br /> char data;<br /> int left;<br /> int right;<br /> };<br /> int n;<br /> Node node[1001]; </p> <p>void preorder(int tmp) {<br /> cout << node[tmp].data;<br /> if(node[tmp].left != 0) preorder(node[tmp].left);<br /> if(node[tmp].right != 0) preorder(node[tmp].right);<br /> }<br /> int main() {<br /> int index;<br /> int head = 0;<br /> while(cin >> n) {<br /> head = 0;<br /> for(int i = 0; i < n; i++) {<br /> cin >> index;<br /> cin >> node[index].data >> node[index].left >> node[index].right;<br /> //找头结点<br /> head = head ^ index ^ node[index].left ^ node[index].right;<br /> }<br /> preorder(head);<br /> cout << endl;<br /> }<br /> return 0;<br /> }