#include <bits/stdc++.h>
using namespace std;
const int MAX = 1001;
const long long MOD = (int)1e9 + 7;
const int INF = 1e9;
const long long LLINF = 0x3f3f3f3f3f3f3f3f;
const long double EPS = 1e-7;
int n, qt, t;
int prox[MAX][9][MAX];
int tab[MAX][MAX], tempo[MAX][MAX];
vector<int> v;
int dp(int i, int mask) {
  if (mask >= (1 << 8) - 1) return 0;
  if (i >= n) return -INF;
  if (tempo[i][mask] == t) return tab[i][mask];
  tempo[i][mask] = t;
  int res = -INF, val = v[i];
  if (((1 << val) & mask) == 0) {
    int p = prox[i][v[i]][qt];
    int p2 = prox[i][v[i]][qt + 1];
    if (p != -1) res = max(res, qt + dp(p + 1, mask | (1 << val)));
    if (p2 != -1) res = max(res, qt + 1 + dp(p2 + 1, mask | (1 << val)));
  }
  res = max(res, dp(i + 1, mask));
  return tab[i][mask] = res;
}
int32_t main() {
  memset(tab, -1, sizeof(tab));
  memset(prox, -1, sizeof(prox));
  cin >> n;
  v.assign(n, 0);
  vector<int> tmp(8, 0);
  int res = 0;
  for (int i = 0; i < (int)n; i++) {
    cin >> v[i];
    v[i]--;
    if (tmp[v[i]] == 0) {
      res++;
    }
    tmp[v[i]]++;
  }
  for (int val = 0; val <= 7; val++) {
    for (int i = 0; i < n; i++) {
      int qt = 0;
      prox[i][val][0] = i - 1;
      for (int j = i; j < n; j++) {
        if (v[j] == val) {
          qt++;
          prox[i][val][qt] = j;
        }
      }
    }
  }
  int menor = INF;
  for (int i = 0; i < (int)8; i++) {
    menor = min(menor, tmp[i]);
  }
  int l = 1, r = n;
  t = 1;
  while (l <= r) {
    int mid = (l + r) / 2;
    qt = mid;
    int ret = dp(0, 0);
    if (ret >= 0) {
      l = mid + 1;
      res = max(res, ret);
    } else {
      r = mid - 1;
    }
    t++;
  }
  cout << res << '\n';
  return 0;
}
