#include<bits/stdc++.h> #define fi first #define se second #define pb push_back using namespace std; int tab[1000009], per[1000009]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); long long n, a, b, c, wyn = 1, l, r; cin>>n; for(int i=1; i<=n; i++) { cin>>tab[i]; per[tab[i]] = i; if(tab[i] == n) a = i; } l = r = a; for(int k=2; k<=n; k++) { a = per[n - (k/2)]; if(l > a) l = a; if(r < a) r = a; if(r - l + 1 == k) wyn++; if(r - l + 1 < k) { a = max(r - k + 1, 1LL * 1); b = min(l + k - 1, n); c = b - a + 1 - k + 1; wyn += c; } } cout<<2*n+1<<" "<<wyn; 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 | #include<bits/stdc++.h> #define fi first #define se second #define pb push_back using namespace std; int tab[1000009], per[1000009]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); long long n, a, b, c, wyn = 1, l, r; cin>>n; for(int i=1; i<=n; i++) { cin>>tab[i]; per[tab[i]] = i; if(tab[i] == n) a = i; } l = r = a; for(int k=2; k<=n; k++) { a = per[n - (k/2)]; if(l > a) l = a; if(r < a) r = a; if(r - l + 1 == k) wyn++; if(r - l + 1 < k) { a = max(r - k + 1, 1LL * 1); b = min(l + k - 1, n); c = b - a + 1 - k + 1; wyn += c; } } cout<<2*n+1<<" "<<wyn; return 0; } |