#include <iostream>
#include <stack>
#include <math.h>
using namespace std;
void print(int n)
{
int max = (int)pow((double)2,(double)n);
unsigned int mask = 0x00000001;
int i,j;
stack<int> stack1;
for(i=0;i<max;i++)
{
for(j=0;j<n;j++)
{
stack1.push(i&mask?1:0);
mask<<=1;
}
while(stack1.size())
{
cout<<stack1.top();
stack1.pop();
}
cout<<endl;
mask>>=n;
}
}
int main()
{
cout<<"请输入长度n:";
int n;
cin>>n;
cout<<"所有长度为n的二进制串为:"<<endl;
print(n);
return 0;
}