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/*
    I find it wholesome to be alone the greater part of the time.
    To be in company, even with the best, is soon wearisome and dissipating.
    I love to be alone.
    I never found the companion that was so companionable as solitude.
*/
#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define faster ios_base::sync_with_stdio(0); cin.tie(0);
#define int long long
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair <int, int>;
mt19937_64 Rand(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e5 + 1;
//const int Mod = 1e9 + 7;
//const ll inf = 0x3f3f3f3f3f3f3f3f;
int n;
vector <int> S[maxN];
int a[maxN];
int dp[maxN];
ll ans;
ll calc(int i, int j, int k){
    i = min(i, k - 1);
    j = min(j, k - 1);
    ll res = 0;
    if (k <= 0) return 0;
    int i1 = min(i, k - j - 1);
    res += 1LL * (j + 1) * max(0LL, i1 + 1);
    i1 = max(i1 + 1, 0LL);
    j = k - 1 - i1;
    if (j < 0) return res;
    int aa = i1 + 1;
    int bb = j + 1;
    int x = min(i + 1 - aa, bb - 1);
    // (i1 -> i) * (j - 1 -> j - x)
    res += 1LL * (x + 1) * aa * bb + x * (x + 1) * (bb - aa) / 2 + x * (x + 1) * (2 * x + 1) / 6;
    return res;
}
void Light(int c){
    for (int i = 0; i < signed(S[c].size()); ++i){
        for (int j = i; j < signed(S[c].size()); ++j){
            int l = i ? S[c][i - 1] : 0;
            int r = (j + 1 == S[c].size()) ? n + 1 : S[c][j + 1];
            int k = (j - i + 1) - (S[c][j] - S[c][i] - j + i);
            ans += calc(S[c][i] - l - 1, r - S[c][j] - 1, k);
        }
    }
}
void Heavy(int c){
    fill(dp, dp + 2 * n + 2, 0);
    int cur = n + 1;
    for (int i = 1; i <= n; ++i){
        if (a[i] == c){
            ++cur;
            dp[cur] += dp[cur - 1];
        }
        else{
            dp[cur] -= dp[cur - 1];
            --cur;
        }
        ++dp[cur];
        ans += dp[cur - 1];
    }
}
void Init(){
    cin >> n;
    vector <int> node;
    for (int i = 1; i <= n; ++i){
        cin >> a[i];
        node.pb(a[i]);
    }
    sort(node.begin(), node.end());
    node.resize(unique(node.begin(), node.end()) - node.begin());
    for (int i = 1; i <= n; ++i){
        a[i] = upper_bound(node.begin(), node.end(), a[i]) - node.begin();
        S[a[i]].pb(i);
    }
    for (int i = 1; i <= n; ++i){
        if (S[i].empty()) continue;
        if (S[i].size() <= 318) Light(i);
        else Heavy(i);
    }
    cout << ans;
}
#define debug
#define taskname "test"
signed main(){
    faster
    if (fopen(taskname".inp", "r")){
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    int tt = 1;
    //cin >> tt;
    while (tt--){
        Init();
    }
    if (fopen("timeout.txt", "r")){
        ofstream timeout("timeout.txt");
        timeout << signed(double(clock()) / CLOCKS_PER_SEC * 1000);
        timeout.close();
        #ifndef debug
        cerr << "Time elapsed: " << signed(double(clock()) / CLOCKS_PER_SEC * 1000) << "ms\n";
        #endif // debug
    }
}
컴파일 시 표준 에러 (stderr) 메시지
Main.cpp: In function 'void Light(long long int)':
Main.cpp:49:28: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |             int r = (j + 1 == S[c].size()) ? n + 1 : S[c][j + 1];
      |                      ~~~~~~^~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen(taskname".out", "w", stdout);
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