#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
using namespace std;

int solve(string S, int i) {
	int ans = 1;
	for (int j = 1;; j++) {
		if (i - j < 0 || i + j >= S.size())break;

		if (S[i - j] == S[i + j])ans += 2;
	}

	return ans;
}

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

	int ans = 1;
	for(int i=0;i<S.size();i++){
		ans = max(ans, solve(S, i));
	}
	cout << ans << endl;

    return 0;
}