Interesting Array

#include <iostream>
#include <unordered_map>

using namespace std;

const int NMAX = 1e5;
int N, a[NMAX + 2];
long long sol = 1LL;

void Solve(int L, int R)
{
    unordered_map <int, int> fr;

    for(int i = L; i <= R; i++)
        fr[a[i]]++;

    int maxFq = 0, minFq = R - L + 2;

    for(auto it : fr)
    {
        maxFq = max(maxFq, it.second);
        minFq = min(minFq, it.second);
    }

    sol = max(sol, 1LL * maxFq * minFq);

    int l = -1;
    for(int i = L; i <= R; i++)
        if(fr[a[i]] == minFq)
        {
            if(l != -1)
            {
                Solve(l, i - 1);
                l = -1;
            }
        }
        else
        {
            if(l == -1)
                l = i;
        }

    if(l != -1)
        Solve(l, R);
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> N;
    for(int i = 1; i <= N; i++)
        cin >> a[i];

    Solve(1, N);

    cout << sol << '\n';

    return 0;
}