#include <bits/stdc++.h>

using namespace std;
#define int long long
const int N=1;
int n;
string s;

signed main()
{
	cin>>n;
	int i=0;
	while(n>0){
		s[i++]=n%10+'0';
		n/=10;
	}
	cout<<s;
	return 0;
}

为啥没有输出？？？