fork(2) download
copy 
  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. #define ll long long
  4. #define maxn 100005
  5. ll a[maxn];
  6. ll i, j, k, n, m, res, sum;
  7. map<ll, vector<ll>> mapping;
  8. ll solve(vector<ll> u)
  9. {
  10.     sort(u.begin(), u.end());
  11.     ll pre_sum[u.size()];
  12.     memset(pre_sum, 0, sizeof(pre_sum));
  13.     pre_sum[0] = u[0];
  14.     for (ll i = 1; i < u.size(); i++)
  15.         pre_sum[i] = pre_sum[i - 1] + u[i];
  16.     ll tong = 0;
  17.     for (ll n = u.size() - 1; n >= 1; n--)
  18.     {
  19.         tong = tong + n * u[n] - pre_sum[n - 1];
  20.     }
  21.     return tong;
  22. }
  23. int main()
  24. {
  25.     cin >> n;
  26.     for (i = 0; i < n; i++)
  27.     {
  28.         ll x;
  29.         cin >> x;
  30.         mapping[x].push_back(i);
  31.     }
  32.     for (auto p : mapping)
  33.     {
  34.         if (p.second.size() >= 2)
  35.         {
  36.             res = res + solve(p.second);
  37.         }
  38.     }
  39.     cout << res;
  40.     return 0;
  41. }
Success #stdin #stdout 0s 4924KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Standard output is empty
https://ideone.com/nPSyJ7
language:
C++14 (gcc 8.3)
created:
3 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!