#include<bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define reps(i,s,n) for(int i=(int)(s);i<(int)(n);i++)
const ll mod = 1e9 + 7;
const int INF = 1e9;

int main() {
	cin.sync_with_stdio(false);
	deque<char>que;
	string s;
	cin >> s;
	rep(i, s.size())que.push_back(s[i]);
	int cnt = 0;
	while (!que.empty()) {
		if (que.size() == 1) {
			cnt++;
			break;
		}
		if (que.front() == que.back())cnt+=2;
		que.pop_back();
		que.pop_front();
	}
	reps(i,1, s.size()-1) {
		int cnt2 = 1;
		reps(j,1, min(i,(int)s.length() - i)){
			if (s[i + j] == s[i - j]) {
				cnt2+=2;
			}
		}
		cnt = max(cnt, cnt2);
	}
	cout << cnt << endl;
	return 0;
}