#include <stdio.h>

#include <stdlib.h>

#pragma warning (disable: 4996)

typedef struct treeNode *tree_pointer;

typedef struct treeNode {

char key;

tree_pointer left_child;

tree_pointer right_sibling;

}treeNode;

tree_pointer createNode(char key) {

tree_pointer newNode = (tree_pointer)malloc(sizeof(treeNode));

newNode->left_child = NULL;

newNode->right_sibling = NULL;

newNode->key = key;

return newNode;

}

int main(void) {

char data[50] = { 0 };

int i = 0;

tree_pointer node[52];

scanf("%s", data);

while (data[i] != 0) {

if (i == 0)

node[i] = createNode(data[i]);

i++;

}

return 0;

}

빨간 부분에서 오류가 나네요

혹시 어떻게 고쳐야하는지 여쭤봐도 될까요????