没分给之2

[wyqiang]

#include<stdio.h>
#include<malloc.h>
typedef struct bitree{
struct bitree *rig,*lef;
char data;
int flag;
char p;
}*tree,treenote;
treenote btrees;

char *ch;
char *prestr;
void creat(tree& btree,char censtr[])
{
int i;
char soncen[20];
if((*prestr)!='\0' && censtr[0]!='\0'){

int flag=1;
int k;
for(i=0;censtr[i]!='\0';i++) if
(censtr[i]==*prestr)
{ flag=0;break;}
if(!flag)
{ btree->data=*prestr++;

for(k=0;k<i;k++) soncen[k]=censtr[k];
soncen[k]='\0';

btree->lef=(tree)malloc(sizeof(treenote));
btree->rig=(tree)malloc(sizeof(treenote));
creat(btree->lef,soncen);
creat(btree->rig,censtr+i+1);
}
else {btree->lef=NULL;btree->rig=NULL;}

}
else {btree->data='#';btree=NULL;}
}
void preorder(tree btrees)
{
if (btrees)
{ printf("%c",btrees->data);
preorder(btrees->lef);
preorder(btrees->rig);

}
else printf("%c",'*');
}
void main()
{char censtr[20];
char pre[20];
tree tr[40],tp;
int base,top;
printf("enter the preorder:\n");
gets(pre);
prestr=pre;
printf("enter the centralorder:\n");
gets(censtr);
creat(&btrees,censtr);
preorder(&btrees);
}