1883F - You Are So Beautiful - CodeForces Solution

#include<bits/stdc++.h>
#include<math.h>
#define    ll    long long   int
#define ull unsigned long long int
#include <ext/pb_ds/detail/standard_policies.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

typedef tree< ll, null_type, less<ll >, rb_tree_tag, tree_order_statistics_node_update> order_set;
#define fbo find_by_order
#define ook order_of_key
#define    F     first
#define    S    second
#define    all(x) (x).begin(),(x).end()
#define    print(res) cout<<#res<<" = ";for(auto x:res) cout<<x<<" "; cout<<endl
#define    see(res) cout<<#res<<" = "<<res<<endl
#define    fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define    pf      push_front
#define    pb      push_back
#define    NL      printf("\n")
#define    YES       printf("YES\n")
#define    NO        printf("NO\n")
#define    Yes       printf("Yes\n")
#define    No        printf("No\n")
#define tc int tc;scanf("%d",&tc);for(int cs=1;cs<=tc;cs++)

const ll mxn=2e6+6;
const ll mod=1e9+7;
const ll N=2e5+10;


int main( )

{


    tc

    {

        ll n ;
        cin>>n ;
        map<ll,ll>m1;
        map<ll,ll>m2;
        ll a[n+10] ;
        for(ll i=1 ; i<=n ; i++)
        {
            cin>>a[i];
            m1[a[i]]++ ;
        }

        ll ans = 0;
        ll extra = 0 ;
        ll cnt = 1;
        for(ll i=n ; i>=1 ; i--)
        {
            if(m2[a[i]]) ++extra;
            --m1[a[i]];
            ++m2[a[i]];
            if(m1[a[i]]==0) ans+=(cnt-extra);
            ++cnt;

        }

        cout<<ans<<endl;
        cout<<endl;

    }

    return 0;
}

//printf("Case %d: ",cs);