#include<iostream>
#include<stdlib.h>
#define S_size 100
using namespace std;
typedef struct aa
{
    int top;
    int a[S_size];
}LinkStack;
void Initstack(LinkStack *S)
{//初始化栈
    S->top=-1;
}
void Clearstack(LinkStack *S)
{//清空栈
    S->top=-1;
}
void Pushstack(LinkStack *S,int *elem)
{//进栈
    if(S->top==S_size-1)
    {
        cout<<"上溢出!"<<endl;
        exit(1);
    }
    else
    {
        S->top++;
        S->a[S->top]=*elem;
    }
}
void Popstack(LinkStack *S,int *w)
{//出栈
    if(S->top==-1)
    {
        cout<<"下溢出！"<<endl;
        exit(1);
    }
    else
    {
        *w=S->a[S->top];
        S->top--;
    }
}
int Gettop(LinkStack *S)
{//取栈顶元素
    if(S->top==-1)
    {
        cout<<"下溢出！"<<endl;
        exit(1);
    }
    else
        return S->a[S->top];
}
int Emptystack(LinkStack *S)
{//判断栈是否为空
    if(S->top==-1)
        return 1;
    else
        return 0;
}
void transformstack(long m)
{//转化为二进制数
    LinkStack *P;
    Initstack(P);
    int *b,*c;
    while(m!=0)
    {
        *b=m%2;
        Pushstack(P,b);
        m=m/2;
    }
    while(!Emptystack(P))
    {
        Popstack(P,c);
        cout<<(*c);
    }
    cout<<"\n"<<endl;
}
int main()
{
    long n;
    cin>>n;
    transformstack(n);
    return 0;
}
//不知道为什么没有输出，求大神帮忙

    LinkStack *P;
    Initstack(P);
    int *b,*c;
    while(m!=0)
    {
        *b=m%2;
这是什么东西呀，根本看不懂

#include <iostream>
#include <stack>
using namespace std;

void foo( unsigned m )
{
    stack<unsigned> s;
    for( ; m!=0; m/=2 )
        s.push( m%2 );

    if( s.empty() )
        cout << 0;
    else
        for( ; !s.empty(); s.pop() )
            cout << s.top();
    cout << endl;
}
int main( void )
{
    unsigned n;
    cin >> n;
    foo( n );

    return 0;
}