#include <cstdio>
#include <cstring>

using namespace std;
char s[550];

int main()
{
    int N;
    freopen("palm.in","r",stdin);
    freopen("palm.out","w",stdout);

    fgets(s,550,stdin);
    N=strlen(s);

    int w,x=1;
    for(int i=0;i<N;++i)
    {
        w=0;
        int j=1;
        while((s[i-j]==s[i+j])&&(i-j>=0)&&(i+j<N)&&(s[i-j]<=s[i-j+1]))
        {
            ++j;
            ++w;
        }
        if(w*2+1>x) x=w*2+1;
    }

    printf("%d\n",x);

    return 0;
}