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c_cpp
2 years ago
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#include "bits/stdc++.h"
using namespace std;

using ll = long long;
using ull = unsigned long long;
using db = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<db, db>;
using tiii = tuple<int, int, int>;
using str = string;

#define vt vector
#define pb push_back
#define eb emplace_back
#define ins insert
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()

#define mp make_pair
#define mt make_tuple
#define fi first
#define se second

constexpr int maxN = 1e5;

vt<int> parent(maxN), s(maxN, 1);

int leader(int v) {
    return (parent[v] == v ? v : parent[v] = leader(parent[v]));
}

void merge(int a, int b) {
    a = leader(a);
    b = leader(b);
    if (s[a] < s[b]) swap(a, b);
    s[a] += s[b];
    parent[b] = a;
}

void solve() {
    iota(all(parent), 0);
    int n;
    cin >> n;
    vt<int> p(n);
    vt<int> inds(n);
    for (int i = 0; i < n; i++) {
        cin >> p[i];
        p[i]--;
        inds[p[i]] = i;
    }
    ll ans = 0;
    for (int i = 0; i < n; i++) {
        ll cntL = 1, cntR = 1;
        int id = inds[i];
        if (id > 0 && i > p[id - 1]) {
            cntL += s[leader(p[id - 1])];
            merge(i, p[id - 1]);
        }
        if (id < n - 1 && i > p[id + 1]) {
            cntR += s[leader(p[id + 1])];
            merge(i, p[id + 1]);
        }
        ans += cntL * cntR * (i + 1);
    }
    cout << ans;
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);
    int tests = 1;
    // cin >> tests;
    while (tests--) {
        solve();
    }
    return 0;
}
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