#include <iostream>
#include <cstdlib>
#include <string>
using namespace std;
int main()
{
string a,b;
long int length;
bool t=0;
while(cin >> a)
{
length = a.size();
for(long int i=0;i<length;i++)
{
b[length-1-i]=a[i];
}
for(long int j=0;j<length;j++)
{
//cout << "a=" << a[j] << "\n";
//cout << "b=" << b[j] << "\n";
if(a[j]==b[j])
{
t=1;
}
else
{
t=0;
}
}
if(t==1)
{
cout << "yes" << "\n";
t=0;
}
else
{
cout << "no" << "\n";
t=0;
}
}
return 0;
}