请说明下列算法中的Unknown1、Unknown2 和Unknown3 的功能。如果Unknownl的输入数据为(20_13_1_0_5_3_0_0_8_0_0 _0 30_0_0), 其中“_”表示空格，那么整个程序将建立一个什么样的结构，最后的输出是什么?
#include <stdlib.h>
#include <stdio.h>
#defineOK 1
#define ERROR 0
#define OVERFLOW 0
int i,count=0;
int A[!00};
typedef int Status;
tpedcf int TElemType;
typedef structs_ BiTNode{
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TElemType data;
structs BiTNode *lchild,*rchild;
} BiTNode, *BiTree;
Status Unknown1(BiTree &T);
Status Unknown2(BiTree *T);
Status Unknown3(BiTree *T);
Status Unknown1(BiTree &Tree)
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TElemType el;
scanf(%d",&el);
if(el==O)
Tree=NULL;
Else
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if(!(Tree=
(BiTree)malloc(sizeof(BiTNode) ) ) )
exit(OVERFLOW);
Tree->data= ei;
Unknown1(Tree-
>lchild);
Unknownl(Tree->rchi!d);
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returr (OK);
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Status Unknown2(BiTreeT)
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if(T)
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Unknown2(T>lchild);
printf(' %d ",T> data);
A[count]=T> data;
Unknown2(T>rchild);
Return OK;
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else
retum OK;3
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Status Unknown3(BiTreeT)
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for(i=0;i<= count-2;iH)[
if(A[i+1])｛
if[A[í]> A[i+l])
return ERROR;
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return OK
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void mainO
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BiTree TrNULL;
Unknown1(Tr);
Unknown2(Tr);
printf("╲n");
int
flag = Unknown3(Tr);
if(fag=0)}{
printf"不是!");
}else f(flag==1){
printf"是!");
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