#include <bits/stdc++.h> using namespace std; typedef unsigned long long ull; typedef long long ll; typedef long double ld; typedef pair<int, int> PII; typedef pair<ll, int> PILL; typedef pair<ll, ll> PLL; const int MAX_N = 1e6+5; const int M = 3e4+5; const ll INF = (ll)(1e18); const int inf = 1e9; const ll MOD = 1000000007LL; int n; int a[MAX_N], pos[MAX_N]; set<int> S; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; pos[a[i]] = i; } ll ways = 0LL; int cur_len = n; int min_needed = (n + 1) / 2; if (n%2 == 0) { ways++; cur_len--; min_needed++; } for (int i = min_needed; i <= n; i++) { S.insert(pos[i]); } while (!S.empty()) { int maxi = *S.rbegin(); int mini = *S.begin(); int min_start = max(1, maxi + 1 - cur_len); int max_start = min(mini, n + 1 - cur_len); ways += max(max_start - min_start + 1, 0); cur_len--; if (cur_len <= 0) break; min_start = max(1, maxi + 1 - cur_len); max_start = min(mini, n + 1 - cur_len); ways += max(max_start - min_start + 1, 0); S.erase(pos[min_needed]); min_needed++; cur_len--; } cout << 2*n+1 << ' ' << ways << '\n'; 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 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 | #include <bits/stdc++.h> using namespace std; typedef unsigned long long ull; typedef long long ll; typedef long double ld; typedef pair<int, int> PII; typedef pair<ll, int> PILL; typedef pair<ll, ll> PLL; const int MAX_N = 1e6+5; const int M = 3e4+5; const ll INF = (ll)(1e18); const int inf = 1e9; const ll MOD = 1000000007LL; int n; int a[MAX_N], pos[MAX_N]; set<int> S; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; pos[a[i]] = i; } ll ways = 0LL; int cur_len = n; int min_needed = (n + 1) / 2; if (n%2 == 0) { ways++; cur_len--; min_needed++; } for (int i = min_needed; i <= n; i++) { S.insert(pos[i]); } while (!S.empty()) { int maxi = *S.rbegin(); int mini = *S.begin(); int min_start = max(1, maxi + 1 - cur_len); int max_start = min(mini, n + 1 - cur_len); ways += max(max_start - min_start + 1, 0); cur_len--; if (cur_len <= 0) break; min_start = max(1, maxi + 1 - cur_len); max_start = min(mini, n + 1 - cur_len); ways += max(max_start - min_start + 1, 0); S.erase(pos[min_needed]); min_needed++; cur_len--; } cout << 2*n+1 << ' ' << ways << '\n'; return 0; } |