#include <bits/stdc++.h> void update_vis(bool *vis, int &it) { while (vis[it]) --it; return; } int main() { std::ios_base::sync_with_stdio(false); std::cin.tie(nullptr); std::cout.tie(nullptr); int n; std::cin >> n; auto *tab = new int [n + 1]; for (int i = 0; i < n; ++i) { int input; std::cin >> input; tab[input] = i; } int l = tab[n], r = tab[n]; long long score = 1; for (int len = 2; len <= n; ++len) { l = std::min(l, tab[n - (len / 2)]); r = std::max(r, tab[n - (len / 2)]); if (r - l + 1 > len) continue; long long sub_r = std::min(l + len - 1, n - 1); long long sub_l = std::max(r - len + 1, 0); score += sub_r - sub_l - len + 2; } std::cout << 2 * n + 1 << " " << score; delete [] tab; 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 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 | #include <bits/stdc++.h> void update_vis(bool *vis, int &it) { while (vis[it]) --it; return; } int main() { std::ios_base::sync_with_stdio(false); std::cin.tie(nullptr); std::cout.tie(nullptr); int n; std::cin >> n; auto *tab = new int [n + 1]; for (int i = 0; i < n; ++i) { int input; std::cin >> input; tab[input] = i; } int l = tab[n], r = tab[n]; long long score = 1; for (int len = 2; len <= n; ++len) { l = std::min(l, tab[n - (len / 2)]); r = std::max(r, tab[n - (len / 2)]); if (r - l + 1 > len) continue; long long sub_r = std::min(l + len - 1, n - 1); long long sub_l = std::max(r - len + 1, 0); score += sub_r - sub_l - len + 2; } std::cout << 2 * n + 1 << " " << score; delete [] tab; return 0; } |