#define  _CRT_SECURE_NO_WARNINGS
#include <iostream>
using namespace std;
#include <algorithm>
#include <string>
#include <vector>
#include <list>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <unordered_set>
#include <unordered_map>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>



int main() {
	int n; cin >> n;
	vector<int>nums(n + 1);
	for (int i = 1; i <= n; i++) {
		cin >> nums[i];
		nums[i] = (nums[i] + nums[i - 1]) % 7;
	}
	int first[7];int last[7];

	for (int i = n; i>=1; i--)
		first[nums[i]] = i;
	first[0] = 0;

	for (int i = 1; i <= n; i++) {
		last[nums[i]] = i;
	}
	int mx = -1;
	for (int i = 0; i < 7; i++) {
		mx = max(mx, last[i] - first[i]);
	}

	cout << mx << endl;

	return 0;
}