1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
#include <bits/stdc++.h>
using namespace std;
#define ll long long

//zmienne
const ll N = 5e5+3;
ll n, k;
ll am = 0;

//kontenery
int used[N];

//funkcje
//**********************************

//**********************************

int main()
{
  scanf("%lli %lli", &n, &k);

  ll s;
  ll res1 = 0;
  ll res2 = 0;

  for (ll i = 0; i < n; i++)
  {
    scanf("%i", &s);

    if (k > 0)
    {
      if (used[s] != 0)
      {
        am++;
        res1 += i;
      }
      else //used[s] == 0
      {
        used[s]++;
      }
      k--;
    }
    else //k == 0
    {
      if (am > 0)
      {
        if (used[s] == 0)
        {
          res2 += i;
          am--;
        }
      }
    }
  }

  if (am > 0)
  {
    printf("-1");
  }
  else
  {
    printf("%lli", (res2-res1) );
  }

return 0;
}