主函数中push和pop不能声明

#include<stdio.h>
#include<stdlib.h>
#define MAXSIZE 100
#define OK 1
#define ERROR 0
typedef int DataType;
typedef struct{
DataType data[MAXSIZE];
int top;
}SeqStack,*PSeqStack;
PSeqStack Init_SeqStack(void){
PSeqStack S;
S=(PSeqStack)malloc(sizeof(SeqStack));
if(S)
S->top=-1;
return S;
}
int Empty_SeqStack(PSeqStack S){
if(S->top==-1)
return 1;
else return 0;
}
int Push_SeqStack(PSeqStack S,DataType x){
if(S->top==MAXSIZE-1)
return 0;
else
{
S->top++;
S->data[S->top]=x;
return 1;
}
}
int Pop_SeqStack(PSeqStack S,DataType *x){
if(Empty_SeqStack(S))
return 0;
else{
*x=S->data[S->top] ;
S->top--;
return 1;
}
}
int main(){
PSeqStack S;
Init_SeqStack();
Empty_SeqStack(S);
int n=0,a,b,x;
printf("请输入一个整数n:",n);
scanf("%d",&n);
do{
a=n/2;
b=n%2;
Push_SeqStack(S,b);
n=a;
}while(a>0);
Pop_SeqStack(S,b);
return(0);
}报错在说push和Pop说明声明

#include<stdio.h>
#include<stdlib.h>
#define MAXSIZE 100
#define OK 1
#define ERROR 0

typedef int DataType;
typedef struct{
    DataType data[MAXSIZE];
    int top;
}SeqStack,*PSeqStack;

PSeqStack Init_SeqStack(void){
    PSeqStack S;
    S=(PSeqStack)malloc(sizeof(SeqStack));
    if(S)
        S->top=-1;
    return S;
}

int Empty_SeqStack(PSeqStack S){
    if(S->top==-1)
        return 1;
    else 
        return 0;
}

int Push_SeqStack(PSeqStack S,DataType* x){
    if(S->top==MAXSIZE-1)
        return 0;
    else
    {
        S->top++;
        S->data[S->top] = *x;
        return 1;
    }
}
int Pop_SeqStack(PSeqStack S,DataType *x){
    if(Empty_SeqStack(S))
        return 0;
    else
    {
        *x=S->data[S->top] ;
        S->top--;
        return 1;
    }
}

int main()
{
    //PSeqStack S;
    int* b = 0;
    Empty_SeqStack(Init_SeqStack());
    int n = 0, a;
    printf("请输入一个整数n:",n);
    scanf("%d",&n);
    do{
        a=n/2;
        *b=n%2;
        Push_SeqStack(Init_SeqStack(),b);
        n=a;
    }while(a>0);
    Pop_SeqStack(Init_SeqStack(),b);
    return(0);
}

你这个要实现什么？？？？