函数接口定义：
Stack CreateStack( int MaxSize );
bool Push( Stack S, ElementType X, int Tag );
ElementType Pop( Stack S, int Tag );
其中Tag是堆栈编号，取1或2；MaxSize堆栈数组的规模；Stack结构定义如下：

typedef int Position;
struct SNode {
ElementType *Data;
Position Top1, Top2;
int MaxSize;
};
typedef struct SNode *Stack;
注意：如果堆栈已满，Push函数必须输出“Stack Full”并且返回false；如果某堆栈是空的，则Pop函数必须输出“Stack Tag Empty”（其中Tag是该堆栈的编号），并且返回ERROR。

裁判测试程序样例：
#include <stdio.h>
#include <stdlib.h>

#define ERROR 1e8
typedef int ElementType;
typedef enum { push, pop, end } Operation;
typedef enum { false, true } bool;
typedef int Position;
struct SNode {
ElementType *Data;
Position Top1, Top2;
int MaxSize;
};
typedef struct SNode *Stack;

Stack CreateStack( int MaxSize );
bool Push( Stack S, ElementType X, int Tag );
ElementType Pop( Stack S, int Tag );

Operation GetOp(); /* details omitted /
void PrintStack( Stack S, int Tag ); / details omitted */

int main()
{
int N, Tag, X;
Stack S;
int done = 0;

scanf("%d", &N);
S = CreateStack(N);
while ( !done ) {switch( GetOp() ) {case push: scanf("%d %d", &Tag, &X);if (!Push(S, X, Tag)) printf("Stack %d is Full!\n", Tag);break;case pop:scanf("%d", &Tag);X = Pop(S, Tag);if ( X==ERROR ) printf("Stack %d is Empty!\n", Tag);break;case end:PrintStack(S, 1);PrintStack(S, 2);done = 1;break;}
}
return 0;

/* 你的代码将被嵌在这里 */
输入样例：
5
Push 1 1
Pop 2
Push 2 11
Push 1 2
Push 2 12
Pop 1
Push 2 13
Push 2 14
Push 1 3
Pop 2
End
输出样例：
Stack 2 Empty
Stack 2 is Empty!
Stack Full
Stack 1 is Full!
Pop from Stack 1: 1
Pop from Stack 2: 13 12 11

Stack CreateStack( int MaxSize )
{struct SNode *S=NULL;S=(struct SNode *)malloc(sizeof(struct SNode));S->Data=(int *)malloc(MaxSize*sizeof(int));S->Top1=-1;S->Top2=MaxSize;S->MaxSize=MaxSize;return S;
}
bool Push( Stack S, ElementType X, int Tag )
{if(S->Top2-S->Top1==1){printf("Stack Full\n");return false;}else{if(Tag==1) S->Data[++(S->Top1)]=X;else if(Tag==2) S->Data[--(S->Top2)]=X;return true;}
}
ElementType Pop( Stack S, int Tag )
{if(Tag==1){if(S->Top1==-1){printf("Stack %d Empty\n",Tag);return ERROR;}else return S->Data[(S->Top1)--];}else if(Tag==2){if(S->Top2==S->MaxSize){printf("Stack %d Empty\n",Tag);return ERROR;}else {return S->Data[(S->Top2)++];}}
}