用顺序栈将十进制变为二进制

#include <stdio.h>
#include <stdlib.h>
#define M 100
typedef struct
{
    int data[M];
    int top;
}a;

void InitStack(a *s)
{
    s->top = -1;
}

int Push(a *s,int e)
{
    if (s->top == M-1)
    {
        printf("栈满\n");
        return 0;
    }
    s->top++;
    s->data[s->top]=e;
    return 1;
}

int Empty(a *s)
{
    return(s->top==-1);
}

int Pop(a *s,int *e)
{
    if(Empty(s))
    {
        printf("\n a is free");
        return 0;
    }
    *e=s->data[s->top];
    s->top--;
    return 1;
}

void Conversion(int N)
{
    int e;
    a *s = (a *)malloc(sizeof(a));
    InitStack(s);
    while(N)
    {
        Push(s,N%2);
        N=N/2;
    }
    while(!Empty(s))
    {
        Pop(s,&e);
        printf("%d",e);
    }
}

int main()
{
    int m; 
    printf("输入需要转换的数值: ");
                    scanf("%d",&m);
                    printf("转换为二进制值为: ");
                    Conversion(m);
                    printf("\n");
        }