#include <bits/stdc++.h>   using namespace std;   const int maxn = 2e5 + 10;   int n, a[maxn], cnt[maxn], mx = 0, last[maxn * 2], ans = 0;   void solve1(int x) {     for (int i = 1; i <= n; i++) last[n - i] = last[n + i] = -1;     last[n] = 0;     int cur = 0;     for (int i = 1; i <= n; i++) {       if (a[i] == x)         cur++;       else if (a[i] == mx)         cur--;       if (last[n + cur] == -1)         last[n + cur] = i;       else         ans = max(ans, i - last[n + cur]);     }   }   void solve2(int x) {     for (int i = 1; i <= n; i++) cnt[i] = 0;     int l = 1, equal = 0;     cnt[a[l]]++;     if (cnt[a[l]] == x) equal++;     for (int i = 2; i <= n; i++) {       cnt[a[i]]++;       if (cnt[a[i]] == x)         equal++;       else if (cnt[a[i]] > x) {         while (cnt[a[i]] > x) {           cnt[a[l]]--;           if (cnt[a[l]] == x - 1) equal--;           l++;         }       }       if (equal >= 2) ans = max(ans, i - l + 1);     }   }   int main() {     cin >> n;     for (int i = 1; i <= n; i++) {       cin >> a[i];       cnt[a[i]]++;       mx = cnt[mx] < cnt[a[i]] ? a[i] : mx;     }     int limt = sqrt(n);     for (int i = 1; i <= n; i++)       if (cnt[i] >= limt && i != mx) solve1(i);     for (int i = 1; i < limt; i++) solve2(i);     cout << ans << endl;   }   