题解 | #二叉排序树#

#include <stdio.h>
#include <stdlib.h>


typedef struct Node {
    int val;
    struct Node* left;
    struct Node* right;
} Node ;

void insert(Node* head, int value) {
    if (value < head->val) {
        if (head->left == NULL) {
            Node* pNew =  (Node*)malloc(sizeof(Node));
            pNew->val = value;
            pNew->left = pNew->right = NULL;
            head->left = pNew;
		  //插入节点后，将父节点值输出
            printf("%d\n",head->val);
        } else {
            insert(head->left, value) ;
        }
    } else if (value > head->val) {
        if (head->right == NULL) {
            Node* pNew =  (Node*)malloc(sizeof(Node));
            pNew->val = value;
            pNew->left = pNew->right = NULL;
            head->right = pNew;
            printf("%d\n",head->val);
        } else {
            insert(head->right, value) ;
        }
    }
}


int main() {
    int n;
    while (scanf("%d ", &n) != EOF) { // 注意 while 处理多个 case
        // 64 位输出请用 printf("%lld") to
        int value;
        Node* head = (Node*)malloc(sizeof(Node));
        scanf("%d", &head->val);
        printf("%d\n",-1);
        head->left = head->right = NULL;
        int cnt = 1;
        while (cnt < n) {
            scanf("%d", &value);
            insert(head, value);
            cnt++;
        }
    }
    return 0;
}