```cpp
#include<iostream>
using namespace std;
int main()
{int k,m=0,n=0;cin>>k;
while(k)
{ m=k%10;k=k/10;n=n*10+m;}
cout<<n;
return 0;
}
```
by wcp1325273959 @ 2017-07-22 17:20:32
这题需要额外变量？
```cpp
#include <iostream>
using namespace std;
int main()
{
int num;
cin >> num;
if (!num){
cout << num;
return 0;
}
if (num < 0){
cout << '-';
num = 0-num;
}
while (!(num%10))
num /= 10;
while (num){
cout << num % 10;
num /= 10;
}
return 0;
}
```
by 暮光 @ 2017-07-24 12:58:26
@ tonylzq1不需要using namespace std;
by ezoiHQM @ 2017-07-24 21:40:47