Submission #23599283

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
#define endl "\n"
#define rep(i, n) for (int i = 0; i < n; i++)
//#define sort(v) sort(v.begin(), v.end());
//#define rsort(v) sort(v.rbegin(), v.rend());

void solve()
{
    ll n;
    cin >> n;
    vector<ll> v(n);
    map<ll, ll> m;
    rep(i, n)
    {
        cin >> v[i];
        m[v[i]]++;
    }
    ll sum = n;
    ll res = 0;
    for (int i = 0; i < n; i++)
    {
        res += sum - m[v[i]] - i;
        if (m[v[i]] == 1)
        {
            m[v[i]]--;
            //res++;
        }
        else if (m[v[i]] > 1)
        {
            m[v[i]]--;
        }
    }
    cout << res << endl;
}

int main()
{

#ifndef ONLINE_JUDGE
    freopen("input.in", "r", stdin);
    freopen("output.in", "w", stdout);
#endif
    int t;
    t = 1;
    while (t--)
    {
        solve();
    }
}

Submission Info

Judge Result