TLE in EPALIN

[ankras]

Please let me know any hint why i am getting TLE.

#include <iostream>
#include <string>
using namespace std;
int main()
{
string in,outt;
size_t size;
while(cin>>in)
{
outt="";
size=in.length();
for (size_t i=0,j=size-1; i < size && i<j; i++)
  {
    if(in.at(i) - in.at(j))
    {
      outt = in.at(i) + outt;
    }
    else
    j--;
  }
cout<<in+outt<<endl;
}
return 0;
}