import std.conv, std.functional, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.container, std.math, std.numeric, std.range, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


enum long[] P = [1000000007, 1000000009];
enum LIM = 2 * 10^^5;

int N;
string S;

void main() {
  auto BASE = new long[P.length];
  BASE[0] = 314159265L;
  foreach (h; 1 .. P.length) {
    BASE[h] = (BASE[h - 1] * 123456789L) % 999999937L;
  }
  auto BB = new long[][](P.length, LIM + 1);
  foreach (h; 0 .. P.length) {
    BB[h][0] = 1;
    foreach (i; 0 .. LIM) {
      BB[h][i + 1] = (BB[h][i] * BASE[h]) % P[h];
    }
  }
  
  try {
    for (; ; ) {
      S = readToken();
      N = cast(int)(S.length);
      auto sum0 = new long[][](P.length, N + 1);
      auto sum1 = new long[][](P.length, N + 1);
      foreach (h; 0 .. P.length) {
        foreach (i; 0 .. N) {
          sum0[h][i + 1] = (sum0[h][i] + S[i] * BB[h][i]) % P[h];
          sum1[h][i + 1] = (sum1[h][i] + S[i] * BB[h][N - i]) % P[h];
        }
      }
      int calc(int l, int r) {
        int lo = 0, hi = min(l + 1, N - r) + 1;
        for (; lo + 1 < hi; ) {
          const mid = (lo + hi) / 2;
          bool ok = true;
          foreach (h; 0 .. P.length) {
            const tmpL = (sum0[h][l + 1] - sum0[h][l + 1 - mid]) * BB[h][N - r];
            const tmpR = (sum1[h][r + mid] - sum1[h][r]) * BB[h][l];
            if ((tmpL - tmpR) % P[h] != 0) {
              ok = false;
              break;
            }
          }
          (ok ? lo : hi) = mid;
        }
        debug {
          writeln("calc ", l, " ", r, " = ", lo);
        }
        return lo;
      }
      int ans;
      foreach (i; 0 .. N) {
        foreach (s; 0 .. 2) {
          if (i + s < N) {
            const int a = calc(i, i + s);
            chmax(ans, 2 * a - 1 + s - 1);
            if (0 <= i - a) {
              chmax(ans, 2 * a - 1 + s + 2 * calc(i - a - 1, i + s + a));
            }
            if (i + s + a < N) {
              chmax(ans, 2 * a - 1 + s + 2 * calc(i - a, i + s + a + 1));
            }
          }
        }
      }
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}