请按照下面的核心代码进行更改#include #include struct node{ char info; struct node *llink,*rlink; }; typedef struct node NODE; NODE *creat(){ char x; NODE *p; scanf("%c",&x); printf("%c",x); if(x!='.'){ p=(NODE *)malloc(sizeof(NODE)); p->info=x; p->llink=creat(); p->rlink=creat(); } else p=NULL; return p; } void run(NODE *t){ if(t){ run(t->llink); run(t->rlink); printf("%c",t- >info); } } main() { NODE *T; printf("PLease input a tree:\n"); T=creat(); printf("\n"); if(!T) printf("This is a empty binary tree."); else { printf("The result of post travese is:\n "); run(T); } printf("\n"); }

好的，根据你提供的代码，我们可以将其修改为按照题目要求进行输入和输出的程序。具体的实现可以参考下面的代码：

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

typedef struct node {
    char info;
    struct node *llink, *rlink;
} NODE;

NODE* creat() {
    char x;
    NODE* p;
    scanf("%c", &x);
    if (x == '.') {
        printf(".");
        p = NULL;
    } else {
        p = (NODE*)malloc(sizeof(NODE));
        p->info = x;
        p->llink = creat();
        p->rlink = creat();
    }
    return p;
}

void run(NODE* t) {
    if (t) {
        run(t->llink);
        run(t->rlink);
        printf("%c", t->info);
    }
}

int main() {
    NODE* T;
    printf("Please input a tree:\n");
    T = creat();
    printf("\n");
    if (!T) {
        printf("THIS IS A EMPTY BINARY TREE\n");
    } else {
        printf("The result of post travese is:\n");
        run(T);
        printf("\n");
    }
    return 0;
}

输入样例：ABD..EH...CF.I..G..
输出样例：DHEBIFGCA