#include <iostream>

#include <array>
#include <vector>
#include <list>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <algorithm>

#include <string>
#include <sstream>

#include <memory>
#include <cassert>

#include <functional>

using namespace std;

const int MOD = 1000000007;

typedef unsigned long long ull;

int main()
{
	string s;
	cin >> s;

	if (s.size() == 2) {
		cout << 1 << endl;
		return 0;
	}

	for (int len = s.size(); len >= 2; --len) { // 文字数
		for (int j = 0; j < s.size() - len + 1; ++j) { // 開始位置
			bool isKaibun = false;
			int count = 1;
			for (int k = j; true; ++k) { // 今の位置
				int back = j + len - count;
				if (k == back) {
					isKaibun = true;
					break;
				}
				if (k + 1 == back) {
					if (s[k] == s[back]) {
						isKaibun = true;
					} else {
						isKaibun = false;
					}
					break;
				}
				if (s[k] != s[back]) {
					isKaibun = false;
					break;
				}
				++count;
			}
			if (isKaibun) {
				cout << len << endl;
				return 0;
			}
		}
	}

	cout << 1 << endl;
	return 0;
}