#include <bits/stdc++.h>
#define ll long long
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
using namespace std;
const int N=1e6+5;
ll t[N*4],a[N];
vector <ll> v;
ll get(int v,int tl,int tr,int l,int r){
if(r<tl or tr<l)return 0;
if(l<=tl && tr<=r)return t[v];
int tm=(tl+tr)/2;
return get(v*2,tl,tm,l,r)+get(v*2+1,tm+1,tr,l,r);
}
void update(int v,int tl,int tr,int pos){
if(tl==tr)t[v]++;
else{
int tm=(tl+tr)/2;
if(pos<=tm)update(v*2,tl,tm,pos);
else update(v*2+1,tm+1,tr,pos);
t[v]=t[v*2]+t[v*2+1];
}
}
signed main(){
ios_base::sync_with_stdio();
cin.tie(0);cout.tie(0);
int n,p;
cin>>n;
for(int i=0;i<n;i++)cin>>a[i];
cin>>p;
ll sum=0,x=0,y=0;
for(int i=0;i<n;i++){
x=i;y=p;
x*=y;
v.pb(sum-x);
x=a[i];
sum+=x;
x=i;y=p;
x*=y;
v.pb(sum-x-p);
}
sort(all(v));
v.erase(unique(v.begin(),v.end()),v.end());
sum=0;
ll ans=0;
for(int i=0;i<n;i++){
x=i;y=p;
x*=y;
auto pos=lower_bound(all(v),sum-x)-v.begin();
update(1,1,v.size(),pos+1);
x=a[i];
sum+=x;
x=i;y=p;
x*=y;
pos=lower_bound(all(v),sum-x-p)-v.begin();
ans+=get(1,1,v.size(),1,pos+1);
}
cout<<ans<<"\n";
}
/*
*/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
2648 KB |
Output is correct |
2 |
Correct |
4 ms |
2652 KB |
Output is correct |
3 |
Correct |
4 ms |
2652 KB |
Output is correct |
4 |
Correct |
840 ms |
50112 KB |
Output is correct |
5 |
Correct |
439 ms |
38056 KB |
Output is correct |
6 |
Correct |
681 ms |
48272 KB |
Output is correct |
7 |
Correct |
704 ms |
47904 KB |
Output is correct |
8 |
Correct |
631 ms |
46600 KB |
Output is correct |
9 |
Correct |
786 ms |
49912 KB |
Output is correct |
10 |
Correct |
690 ms |
48184 KB |
Output is correct |