#include <bits/stdc++.h>
#define ll long long int
using namespace std;
const int maxn=1e6+5;
int ind[maxn];
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
cin>>n;
cout<<(n<<1)+1<<" ";
for(int i=1; i<=n; ++i)
{
int a;
cin>>a;
ind[a]=i;
}
if(n==1)
{
cout<<"1";
return 0;
}
ll wyn;
int l=min(ind[n], ind[n-1]), r=max(ind[n], ind[n-1]);
if(r-l==1)
wyn=2;
else
wyn=1;
for(int i=3; i<=n; ++i)
{
l=min(l, ind[n+1-(i/2+1)]);
r=max(r, ind[n+1-(i/2+1)]);
if(r-l+1<=i)
{
wyn+=i-(r-l);
if(r<i)
wyn-=i-r;
if(l>n-i+1)
wyn-=l-(n-i+1);
}
}
cout<<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 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | #include <bits/stdc++.h> #define ll long long int using namespace std; const int maxn=1e6+5; int ind[maxn]; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); int n; cin>>n; cout<<(n<<1)+1<<" "; for(int i=1; i<=n; ++i) { int a; cin>>a; ind[a]=i; } if(n==1) { cout<<"1"; return 0; } ll wyn; int l=min(ind[n], ind[n-1]), r=max(ind[n], ind[n-1]); if(r-l==1) wyn=2; else wyn=1; for(int i=3; i<=n; ++i) { l=min(l, ind[n+1-(i/2+1)]); r=max(r, ind[n+1-(i/2+1)]); if(r-l+1<=i) { wyn+=i-(r-l); if(r<i) wyn-=i-r; if(l>n-i+1) wyn-=l-(n-i+1); } } cout<<wyn; return 0; } |
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