print((bin(int(input())))[2:])

a=int(input())
a=bin(a)
print(a[2:])

print (str(bin(int(input())))[2:])

n=int(input())
s=0
y=0
e=0
m=0

while n>=1:
y=n%2
n=n//2
e=y*10**m+e
m=m+1

print(e)

其实很简单,下面是代码,慢慢看吧
```cpp
#include <iostream>

std::string a = ""; //用string类型来保存数据

int main()
{
unsigned long long n;
std::cin >> n;
unsigned int len = -1; //用来计数,下标从0开始,所以初始值为-1
while (n != 0)
{
a += char(n % 2 + '0'); //把数变成字符存入字符串
len++;
n /= 2; //n每次除以2
}
while (len > 0) //逆向输出
std::cout << a[len--];
std::cout << a[len];
std::cout << std::endl; //回车
return 0;
}
```

#include <stdio.h>
#include <iostream>
using namespace std;
int n,len,e;
int a[64];
int main()
{
    cin>>n;
    while(n)
    {
        a[len++]=(n&1);
        n>>=1;
    }
    for(int i=len-1;i>=0;i--)
    {
        cout<<a[i];
    }
    return 0;
}

a=int(input())
b=bin(a).replace('0b','')
print(b)