#include <algorithm> #include <iostream> #include <vector> using namespace std; int main() { ios_base::sync_with_stdio(0); int n, k, b, i, j; long result = 0; cin >> n >> k; auto visited = vector<bool>(n + 1, false); cin >> b; visited[b] = true; for (i = 0, j = 1; j < n && i + 1 < k; j++) { cin >> b; if (visited[b]) continue; visited[b] = true; result += j - i - 1; i += 1; } cout << (i + 1 == k ? result : -1) << endl; return 0; }
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 | #include <algorithm> #include <iostream> #include <vector> using namespace std; int main() { ios_base::sync_with_stdio(0); int n, k, b, i, j; long result = 0; cin >> n >> k; auto visited = vector<bool>(n + 1, false); cin >> b; visited[b] = true; for (i = 0, j = 1; j < n && i + 1 < k; j++) { cin >> b; if (visited[b]) continue; visited[b] = true; result += j - i - 1; i += 1; } cout << (i + 1 == k ? result : -1) << endl; return 0; } |