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
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
// 2021-1-ora-oranzada.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>

constexpr int MAXN = 1e6;
constexpr int DOD = 1 << 20;
constexpr int SIZ = 2 * DOD + 7;

bool occured[MAXN];
bool taken[MAXN];
int t[MAXN];
int arr[MAXN];

int tree[SIZ];

void tree_incr(int p)
{
	p += DOD;
	while (p > 0)
	{
		tree[p]++;
		p /= 2;
	}
}

long long tree_get(int b, int e)
{
	b += DOD;
	e += DOD;
	if (b==e)
	{
		return tree[b];
	}
	int answ = 0;
	while (b/2 < e/2)
	{
		if (b%2==0)
		{
			answ += tree[b + 1];
		}
		if (e%2==1)
		{
			answ += tree[e - 1];
		}
		b /= 2;
		e /= 2;
	}
	return answ;
}

long long count_swaps(int n)
{
	long long answ = 0;
	for (size_t i = 0; i < n; i++)
	{
		answ += tree_get(arr[i], n + 7);
		tree_incr(arr[i]);
	}
	return answ;
}

int main()
{
	std::ios_base::sync_with_stdio(0);
	std::cin.tie(0);
	std::cout.tie(0);
	int n, k, cnt = 1;
	std::cin >> n >> k;
	for (size_t i = 0; i < n; i++)
	{
		std::cin >> t[i];
		if (!occured[t[i]] && cnt <= k)
		{
			taken[i] = true;
			occured[t[i]] = true;
			arr[i] = cnt;
			cnt++;
		}
	}
	if (cnt <= k)
	{
		std::cout << "-1\n";
		return 0;
	}
	for (size_t i = 0; i < n; i++)
	{
		if (!taken[i])
		{
			arr[i] = cnt;
			cnt++;
		}
	}
	std::cout << count_swaps(n) << '\n';
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file