bool is_valid(char ch)
{
    return ch == 'A' or ch == 'H' or ch == 'I' or ch == 'M' or ch == 'O' or ch == 'T' or ch == 'U' or ch == 'V' or ch == 'W' or ch == 'X' or ch == 'Y';
}

// A, H, I, M, O, T, U, V, W, X, Y

void solve()
{
    string s;
    cin >> s;
    ll l1 = 0, r1 = s.length() - 1, Maxx = 0;
    while (l1 <= r1)
    {
        ll l = l1, r = r1, t = 1, holder = r1;
        while (l <= r)
        {
            if (!is_valid(s[l]) or !is_valid(s[r]) or s[l] != s[r])
            {
                l = l1;
                r = r1 - t++;
                holder = r;
            }
            else
            {
                r--;
                l++;
            }
        }
        Maxx = max(Maxx, holder - l1 + 1);
        l1++;
    }
    cout << Maxx << '\n';
}