#include <bits/stdc++.h>
using namespace std;
int n;
int a[1005];
int dp[1005][(1 << 8) + 1];
int nxt[9][1005][1005];
int X;
int solve(int idx, int mask) {
  if (mask == (1 << 8) - 1) return 0;
  if (dp[idx][mask] != -1) return dp[idx][mask];
  int &ans = dp[idx][mask];
  ans = -100000000;
  for (int i = 0; i < 8; ++i) {
    if (mask & (1 << i)) continue;
    int pos1 = nxt[i][idx][X];
    if (pos1 != -1) ans = max(ans, solve(pos1 + 1, mask | (1 << i)));
    int pos2 = nxt[i][idx][X + 1];
    if (pos2 != -1) ans = max(ans, 1 + solve(pos2 + 1, mask | (1 << i)));
  }
  return ans;
}
bool possible() {
  memset(dp, -1, sizeof(dp));
  if (solve(0, 0) < 0)
    return false;
  else
    return true;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  set<int> s;
  int i, j, k;
  cin >> n;
  for (i = 0; i < n; ++i) {
    cin >> a[i];
    a[i]--;
    s.insert(a[i]);
  }
  for (i = 0; i < 8; ++i) {
    for (k = 0; k < 1005; ++k) {
      for (j = 0; j < 1005; ++j) nxt[i][j][k] = -1;
    }
  }
  for (i = n - 1; i >= 0; --i) {
    for (j = 0; j < 8; ++j) {
      if (a[i] == j)
        nxt[j][i][1] = i;
      else
        nxt[j][i][1] = nxt[j][i + 1][1];
      for (k = 2; k < 1005; ++k) {
        if (a[i] == j)
          nxt[j][i][k] = nxt[j][i + 1][k - 1];
        else
          nxt[j][i][k] = nxt[j][i + 1][k];
      }
    }
  }
  int best = 0;
  int lo = 0, hi = n;
  while (lo <= hi) {
    int mid = (lo + hi) >> 1;
    X = mid;
    if (possible()) {
      best = mid;
      lo = mid + 1;
    } else {
      hi = mid - 1;
    }
  }
  int ans = (int)s.size();
  if (best > 0) {
    memset(dp, -1, sizeof(dp));
    X = best;
    ans = 8 * X + solve(0, 0);
  }
  cout << ans << '\n';
  return 0;
}
