#include <iostream>
#include <cmath>
using namespace std;
int main()
{
int n;
cin >> n;
int *indexes = new int[n+1];
int num;
for (int i=0;i<n;++i)
{
cin >> num;
indexes[num] = i;
}
long long res = 1;
int d = 1;
int start = indexes[n], end = indexes[n];
int l;
for (int i=n-1;i>=1 && d<n;--i)
{
if (indexes[i] < start) start = indexes[i];
if (indexes[i] > end) end = indexes[i];
l = end - start + 1;
++d;
if (d >= l)
{
int dpmin = max(start-d+l,0), dpmax = min(start, n-d);
res += dpmax - dpmin + 1;
}
if (d == n) break;
++d;
if (d >= l)
{
int dpmin = max(start-d+l,0), dpmax = min(start, n-d);
res += dpmax - dpmin + 1;
}
}
cout << 2*n + 1 << " " << res << endl;
delete[] indexes;
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 | #include <iostream> #include <cmath> using namespace std; int main() { int n; cin >> n; int *indexes = new int[n+1]; int num; for (int i=0;i<n;++i) { cin >> num; indexes[num] = i; } long long res = 1; int d = 1; int start = indexes[n], end = indexes[n]; int l; for (int i=n-1;i>=1 && d<n;--i) { if (indexes[i] < start) start = indexes[i]; if (indexes[i] > end) end = indexes[i]; l = end - start + 1; ++d; if (d >= l) { int dpmin = max(start-d+l,0), dpmax = min(start, n-d); res += dpmax - dpmin + 1; } if (d == n) break; ++d; if (d >= l) { int dpmin = max(start-d+l,0), dpmax = min(start, n-d); res += dpmax - dpmin + 1; } } cout << 2*n + 1 << " " << res << endl; delete[] indexes; return 0; } |
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