#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set tree<ll, null_type, less_equal<ll>, rb_tree_tag, tree_order_statistics_node_update>
#define nn "\n"
#define x_x ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define intt int _; cin >> _; while (_--)
#define emp push_back
#define mod 1000000007
#define all(v) v.begin(), v.end()
#define ld long double
#define A first
#define B second
//#define int long long
typedef long long ll;
const ld eps = 1e-27;
// diff between decimals 0.000000001 mt19937 mt(time(nullptr));
ll sgt[4000003]; //int x[4000003];
void upd(int l, int r, int ind, int i) {
if (r<ind||l>ind) return ;
if(l!=r) {
int mid=(l+r)/2; upd(l,mid,ind,i*2+1); upd(mid+1, r, ind, i*2+2);
}
if(l==r&&l==ind) {sgt[i]++; return ;}
sgt[i]=sgt[i*2+1]+sgt[i*2+2];
}
ll sum(int l, int r, int s, int e, int i) {
if(r<s||l>e) return 0;
if(l>=s&&r<=e)return sgt[i];
int mid=(l+r)/2;
return sum(l,mid,s,e,i*2+1)+sum(mid+1, r, s, e, i*2+2);
}
int main() {
x_x
int n; cin>>n; ll p, sm=0, ar[n];
for(auto&i:ar)cin>>i;
cin>>p;
ll ans=0; vector<ll>tr,v;
for(ll i=1; i<=n; i++) {
sm+=ar[i-1]; ll x=-p*i; x+=sm;
tr.emp(x);
}
tr.emp(0); sort(all(tr)); v.emp(tr[0]);
for(auto i:tr) {
if(i!=v.back()) v.emp(i);
}
sm=0; int ind=lower_bound(all(v),0)-v.begin(); upd(0,v.size(), ind,0);
for (ll i=1; i<=n; i++) {
sm+=ar[i-1]; ll x=p*i; x=sm-x;
int j=upper_bound(all(v), x)-v.begin(); --j;
if (j>=0) {
ans+=sum(0, v.size(), 0, j, 0);
}
x=-p*i; x+=sm; j=lower_bound(all(v),x)-v.begin();
upd(0,v.size(),j,0);
}
cout<<ans;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
604 KB |
Output is correct |
2 |
Correct |
3 ms |
604 KB |
Output is correct |
3 |
Correct |
4 ms |
604 KB |
Output is correct |
4 |
Correct |
622 ms |
43004 KB |
Output is correct |
5 |
Correct |
318 ms |
33156 KB |
Output is correct |
6 |
Correct |
549 ms |
37260 KB |
Output is correct |
7 |
Correct |
575 ms |
39636 KB |
Output is correct |
8 |
Correct |
485 ms |
38380 KB |
Output is correct |
9 |
Correct |
670 ms |
40408 KB |
Output is correct |
10 |
Correct |
517 ms |
39720 KB |
Output is correct |