#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define ar array
#define pb push_back
#define ln '\n'
#define int long long
using i64 = long long;
template <class F, class _S>
bool chmin(F &u, const _S &v){
bool flag = false;
if ( u > v ){
u = v; flag |= true;
}
return flag;
}
template <class F, class _S>
bool chmax(F &u, const _S &v){
bool flag = false;
if ( u < v ){
u = v; flag |= true;
}
return flag;
}
struct Fenw{
vector <int> fenw;
int n;
Fenw(int n) : fenw(n + 1, 0), n(n) {}
void upd(int i, int val){
for (; i <= n; i += i & -i ){
fenw[i] += val;
}
}
int get(int i){
int cnt = 0;
for (; i > 0; i -= i & -i ){
cnt += fenw[i];
}
return cnt;
}
int get(int l, int r){
return get(r) - get(l - 1);
}
};
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n; cin >> n;
vector <int> a(n + 1), pf(n + 1);
for ( int i = 1; i <= n; i++ ){
cin >> a[i];
pf[i] = a[i] + pf[i - 1];
}
int P; cin >> P;
vector <ar<int,2>> q;
for ( int i = 0; i <= n; i++ ){
q.pb({pf[i] - P * i, i});
}
sort(all(q));
int ans = 0;
Fenw fn(n + 1);
for ( auto &[val, j]: q ){
ans += fn.get(j + 1);
fn.upd(j + 1, 1);
}
cout << ans;
cout << '\n';
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
860 KB |
Output is correct |
2 |
Correct |
1 ms |
720 KB |
Output is correct |
3 |
Correct |
1 ms |
576 KB |
Output is correct |
4 |
Correct |
261 ms |
45492 KB |
Output is correct |
5 |
Correct |
132 ms |
31140 KB |
Output is correct |
6 |
Correct |
215 ms |
41248 KB |
Output is correct |
7 |
Correct |
218 ms |
43648 KB |
Output is correct |
8 |
Correct |
210 ms |
36980 KB |
Output is correct |
9 |
Correct |
252 ms |
47472 KB |
Output is correct |
10 |
Correct |
248 ms |
41024 KB |
Output is correct |