#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define fr first
#define sc second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pw(x) (1ll << x)
#define sz(x) (int)((x).size())
#define pb push_back
#define endl '\n'
#define mp make_pair
#define vec vector
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
typedef unsigned long long ull;
template <typename T> inline bool umin (T &a, const T &b) { if (a > b) { a = b; return 1; } return 0; }
template <typename T> inline bool umax (T &a, const T &b) { if (a < b) { a = b; return 1; } return 0; }
template <typename T>
using oset = tree<T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
#define int long long
inline void solve () {
int n; cin >> n;
vector <int> a (n);
for (auto &i : a) cin >> i;
map <int, vector <int>> mp;
for (int i = 0; i < n; ++i) mp[a[i]].pb(i);
const int B = 1000;
ll ans = 0;
function <ll(int, int)> sum = [&] (int l, int r) { return (l + r) * 1ll * (r - l + 1) / 2; };
function <ll(int, int, int)> f = [&] (int lx, int ly, int z) {
umin(lx, z); umin(ly, z);
ll res = 0;
int q = z - ly;
res += max(0ll, q * ly);
res += max(0ll, sum(z - ly + 1, lx));
res += min(z, ly);
return res;
};
for (auto &[_, pos] : mp) {
if (sz(pos) <= B) {
for (int i = 0; i < sz(pos); ++i) {
for (int j = i; j < sz(pos); ++j) {
int need = (pos[j] - pos[i] + 1) / 2 + 1;
if (need > j - i + 1) continue;
int lft, rgt;
if (!i) lft = pos[i];
else lft = pos[i] - pos[i - 1] - 1;
if (j + 1 == sz(pos)) rgt = n - pos[j] - 1;
else rgt = pos[j + 1] - pos[j];
int can = (j - i + 1) * 2 - 1 - pos[j] + pos[i] - 1;
ans += f(lft, rgt, can) + 1;
}
}
}
else {
}
}
cout << ans;
}
signed main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
int t = 1; // cin >> t;
while (t--) solve();
return 0;
}
/// n <= 300
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
3328 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
