stuck on palindrome problem

[tdleanz]

I'm failing on my second test:

**
Test: #1, time: 15 ms., memory: 0 KB, exit code: 0, checker exit code: 0, verdict: OK
Input

1

Output

11

Answer

11

Checker Log

ok answer is '11'

Test: #2, time: 0 ms., memory: 0 KB, exit code: 0, checker exit code: 2, verdict: WRONG_ANSWER
Input

10

Output

0110

Answer

1001

Checker Log

wrong output format 0110 is not a valid integer**



http://codeforces.com/problemset/problem/688/B

This is what I have so far

#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>

using namespace std;

int main(){
 
  string a,b;

  cin >> a;
  b=a;
  reverse(a.begin(), a.end());

  cout << a+b << endl;
 
  return 0;
  


}

[tdleanz]

that worked! thanks so much! @gentleguy