Source Code
#include <bits/stdc++.h>
#define ld long double
#define ll long long
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define sz(s)    (int)(s.size())
const ll N = 2e5+3, mod = 1000000007;
const ll OO = 6e18;
const auto EPS = 1e-6;
const auto PI = acos(-1);
using namespace std;
int DX[] = { 1, -1, 0, 0, -1, 1, 1, -1 };
int DY[] = { 0, 0, 1, -1, 1, -1, 1, -1 };
int dx[] = { 1,0,-1,0 } ,dy[] = { 0,1,0,-1 };

void testCase()
{
	int n;
	cin >> n;
	map<ll, ll>mp;
	for(int i=1;i<=n;i++)
	{
		int x; cin >> x;
		mp[x] = i;
	}
	ll res = 0, mn = mp[0], mx = mp[0];
	for(int i=1;i<=n;i++)
	{
		if(mp[i]<mn)
		{
			ll left = mn-mp[i]-1, right = n-mx;
			res += i*(left+right+(left*right)+1);
		}
		else if(mp[i]>mx)
		{
			ll left = mn-1, right = mp[i]-mx-1;
			res += i*(left+right+(left*right)+1);
		}
		mn = min(mn, mp[i]);
		mx = max(mx, mp[i]);
	}
	cout << res << '\n';
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t = 1;   cin >> t;
    for(int tc = 1;tc<=t;tc++)
    {
        //cout << "Case #" << tc << ": ";
        testCase();
    }
    return 0;
}
Copy
Mex MuhammedKhedr
GNU G++17
377 ms
12.8 MB
Accepted