#include <bits/stdc++.h>
using namespace std;
inline int read() {
  char c = getchar();
  int p = 1, ret = 0;
  while ((c < '0') || (c > '9')) {
    if (c == '-') p = -1;
    c = getchar();
  }
  while ((c >= '0') && (c <= '9'))
    ret = (ret << 1) + (ret << 3) + c - '0', c = getchar();
  return ret * p;
}
int n, L, R;
int sum[1005][8];
bool dp[1005][256][8];
struct state {
  int k, s, r;
} q[2500000];
int a[1005];
inline int find(int x, int k) {
  int l = -1, r = n + 1;
  while (r - l > 1) {
    int mid = (l + r) >> 1;
    if (sum[mid][x] >= k)
      r = mid;
    else
      l = mid;
  }
  return r;
}
inline void ins(int x, int y, int z) {
  if (dp[x][y][z]) return;
  dp[x][y][z] = true;
  q[++R] = (state){x, y, z};
}
inline bool check(int p) {
  int r = p % 8, x = p / 8;
  memset(dp, 0, sizeof(dp));
  L = 0;
  R = 1;
  ins(0, 255, r);
  while (R >= L) {
    state t = q[L++];
    for (int i = 0; i < 8; i++)
      if ((1 << i) & t.s) {
        int tmp = find(i, sum[t.k][i] + x);
        if (tmp < t.k) tmp = t.k;
        if (tmp <= n) ins(tmp, t.s ^ (1 << i), t.r);
        if (t.r > 0) {
          tmp = find(i, sum[t.k][i] + x + 1);
          if (tmp <= n) ins(tmp, t.s ^ (1 << i), t.r - 1);
        }
      }
  }
  for (int i = 1; i <= n; i++)
    if (dp[i][0][0]) return true;
  return false;
}
int main() {
  n = read();
  for (int i = 1; i <= n; i++) a[i] = read() - 1;
  for (int i = 1; i <= n; i++)
    for (int j = 0; j < 8; j++)
      if (a[i] != j)
        sum[i][j] = sum[i - 1][j];
      else
        sum[i][j] = sum[i - 1][j] + 1;
  int l = 1, r = n + 1;
  while (r - l > 1) {
    int mid = (l + r) >> 1;
    if (check(mid))
      l = mid;
    else
      r = mid;
  }
  printf("%d", l);
}
