题解 | #二叉树遍历#

#include<iostream>
#include<cstdio>
#include<string>

using namespace std;

struct TreeNode {
	char data;
	TreeNode* leftChild;
	TreeNode* rightChild;
	TreeNode(char c):data(c),leftChild(NULL),rightChild(NULL){}
};

TreeNode* Build(int& position, string str) {
	char c = str[position++];  //当前字符
	if (c == '#') {
		return NULL;
	}
	TreeNode* root = new TreeNode(c);        //创建新结点
	root->leftChild = Build(position, str);  //创建左子树
	root->rightChild = Build(position, str); //创建右子树
	return root;
}

void InOrder(TreeNode* root) {
	if (root == NULL) {
		return;
	}
	InOrder(root->leftChild);
	printf("%c ", root->data);
	InOrder(root->rightChild);
	return;
}

int main() {
	string str;
	while (cin >> str) {
		int position = 0;                       //标记字符串处理位置
		TreeNode* root = Build(position, str);
		InOrder(root);
		printf("\n");
	}
	system("pause");
	return EXIT_SUCCESS;
}
// 64 位输出请用 printf("%lld")