#include <iostream>
#include <string.h>

using namespace std;

char v[12];
int pal[12];
void manacher ( int n )
{
    int mij = 0;
    for ( int i = 1; i <= n; ++i )
    {
        if ( i > mij )
        {
            while ( v[i+pal[i]+1] == v[i-pal[i]-1] && i - pal[i] > 1 && i + pal[i] < n )
                pal[i]++;
        }
        else
        {
            pal[i] = min (mij + pal[mij] - i, pal[mij-(i-mij)]);
            while ( v[i+pal[i]+1] == v[i-pal[i]-1] && i - pal[i] > 1 && i + pal[i] < n )
                pal[i]++;
            if ( i + pal[i] >= mij + pal[mij] )
                mij = i;
        }
    }
}

int main()
{
    cin>>(v+1);
    int len = strlen (v+1);
    manacher(len);
}