#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long int ll;
/*
5
1 4 3 5 2
5x - size 1
5x,4x - size 2
5,4x - size 3
5,4x,3x - size 4
5,4,3x - size 5
*/
int calc_range_count(const int n,const int l,const int r,const int size)
{
const int rl=r-l+1;
const int extra_needed=size-rl;
const int min_left=std::max(1,l-extra_needed);
const int max_left=std::min(l,n-size+1);
const int count=max_left-min_left+1;
return count;
}
int main()
{
int n;
cin>>n;
vector<int> a(n+1);
vector<int> pos(n+1);
vector<bool> mask(n+1,false);
mask[n]=true;
int l,r;
for(int i=1;i<=n;++i)
{
cin>>a[i];
pos[a[i]]=i;
if(a[i]==n)
l=r=i;
}
const int func=n*2+1;
ll result=1;
int range_size=1;
for(int num=n-1;num>=(n+1)/2;--num)
{
if(!mask[num])
{
if(pos[num]>r)
{
while(!mask[num])
mask[a[++r]]=true;
}
else
{
while(!mask[num])
mask[a[--l]]=true;
}
}
++range_size;
if(r-l+1<=range_size)
result+=calc_range_count(n,l,r,range_size);
++range_size;
if(r-l+1<=range_size)
result+=calc_range_count(n,l,r,range_size);
}
cout<<func<<" "<<result;
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 70 71 72 73 74 75 76 77 78 | #include <iostream> #include <vector> #include <algorithm> using namespace std; typedef long long int ll; /* 5 1 4 3 5 2 5x - size 1 5x,4x - size 2 5,4x - size 3 5,4x,3x - size 4 5,4,3x - size 5 */ int calc_range_count(const int n,const int l,const int r,const int size) { const int rl=r-l+1; const int extra_needed=size-rl; const int min_left=std::max(1,l-extra_needed); const int max_left=std::min(l,n-size+1); const int count=max_left-min_left+1; return count; } int main() { int n; cin>>n; vector<int> a(n+1); vector<int> pos(n+1); vector<bool> mask(n+1,false); mask[n]=true; int l,r; for(int i=1;i<=n;++i) { cin>>a[i]; pos[a[i]]=i; if(a[i]==n) l=r=i; } const int func=n*2+1; ll result=1; int range_size=1; for(int num=n-1;num>=(n+1)/2;--num) { if(!mask[num]) { if(pos[num]>r) { while(!mask[num]) mask[a[++r]]=true; } else { while(!mask[num]) mask[a[--l]]=true; } } ++range_size; if(r-l+1<=range_size) result+=calc_range_count(n,l,r,range_size); ++range_size; if(r-l+1<=range_size) result+=calc_range_count(n,l,r,range_size); } cout<<func<<" "<<result; return 0; } |
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