#include <bits/stdc++.h>
using namespace std;
int n, lis[1111], dp[1111][1 << 8];
int solve(int x) {
  for (int i = (0); i <= ((int)(1010) - 1); i++)
    for (int j = (1); j <= ((1 << 8) - 1); j++) dp[i][j] = -1000000007;
  if (!x) {
    int cntt[8];
    memset(cntt, 0, sizeof(cntt));
    for (int i = (1); i <= (n); i++) cntt[lis[i]] = 1;
    int ans = 0;
    for (int i = (0); i <= ((int)(8) - 1); i++) ans += cntt[i];
    return ans;
  }
  for (int i = (1); i <= (n); i++)
    for (int mask = (0); mask <= ((int)((1 << 8)) - 1); mask++)
      for (int las = (0); las <= ((int)(8) - 1); las++)
        if ((1 << las) & mask) {
          int p = i;
          int cnt = 0;
          while (p) {
            if (lis[p] == las) cnt++;
            if (cnt == x) break;
            p--;
          }
          if (p) {
            dp[i][mask] = max(dp[i][mask], x + dp[p - 1][mask ^ (1 << las)]);
            p--;
            while (p) {
              if (lis[p] == las) break;
              p--;
            }
            if (p)
              dp[i][mask] =
                  max(dp[i][mask], x + 1 + dp[p - 1][mask ^ (1 << las)]);
          }
          dp[i][mask] = max(dp[i][mask], dp[i - 1][mask]);
        }
  return max(0, dp[n][(1 << 8) - 1]);
}
int main() {
  ios::sync_with_stdio(false);
  cin >> n;
  for (int i = (1); i <= (n); i++) {
    cin >> lis[i];
    lis[i]--;
  }
  int high = n / 8 + 3;
  int low = 0;
  int ans = 0;
  while (low < high) {
    int chs = (high + low) / 2;
    int tmp = solve(chs);
    ans = max(ans, tmp);
    if (tmp)
      low = chs + 1;
    else
      high = chs;
  }
  cout << ans;
}
