Title Description

Judging whether two sequences are the same binary search tree sequence

Input Description:

Beginning with a number n, (1 <= n <= 20) means there are n judgements to be made, and the input ends when n= 0.
The next line is a sequence with a length less than 10 and contains (0-9) numbers without duplicate numbers. Based on this sequence, a binary search tree can be constructed.
The next n rows have n sequences. Each sequence format is the same as the first sequence. Please determine whether the two sequences can form the same binary search tree.

Output Description:

If the sequence is the same, YES is output, otherwise NO is output.

Example 1

input

2
567432
543267
576342
0

output

YES
NO

#include <iostream>
#include <string>
#include <cstring>
using namespace std;

struct node{
    node * Lchild;
    node * Rchild;
    int num;
}tree[205];

int loc,len;

node * creat(){
    tree[loc].Lchild=tree[loc].Rchild=NULL;
    return &tree[loc++];
}

node * insert_node(node * t, int x){
    if(t==NULL){
        t=creat();
        t->num=x;
        return t;
    }
    else if(x<t->num)   t->Lchild=insert_node(t->Lchild,x);
    else if(x>t->num)   t->Rchild=insert_node(t->Rchild,x);
    return t;
}

void preorder(node * t,char s[]){
    s[len++]=t->num+'0';
    if(t->Lchild)   preorder(t->Lchild,s);
    if(t->Rchild)   preorder(t->Rchild,s);
}

void midorder(node * t,char s[]){
    if(t->Lchild)   midorder(t->Lchild,s);
    s[len++]=t->num+'0';
    if(t->Rchild)   midorder(t->Rchild,s);
}


int main(){
    int n;
    string str;
    char cmp1[21],cmp2[21];
    while(cin>>n){
        if(n==0)    break;
        node * T = NULL;
        loc=0;
        cin>>str;
        for(int i=0;i<str.size();i++)   T=insert_node(T,int(str[i]-'0'));
        len=0;preorder(T,cmp1);midorder(T,cmp1);cmp1[len]='\0';
        while(n--){
            node * T = NULL;
            cin>>str;
            for(int i=0;i<str.size();i++)   T=insert_node(T,int(str[i]-'0'));
            len=0;preorder(T,cmp2);midorder(T,cmp2);cmp2[len]='\0';
            if(strcmp(cmp1,cmp2)!=0)    cout<<"NO"<<endl;
            else cout<<"YES"<<endl;
        }
    }
    return 0;
}