#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
template<typename T>
class fenwick {
private:
vector<int> fenw;
int n;
public:
fenwick(int _n) : n(_n) {
fenw.resize(n);
}
T get(int x) {
T v{};
while (x >= 0) {
v += fenw[x];
x = (x & (x + 1)) - 1;
}
return v;
}
void modify(int x, T v) {
while (x < n) {
fenw[x] += v;
x |= (x + 1);
}
}
};
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
vector<int> a(n);
for (int i = 0; i < n; i++) {
cin >> a[i];
}
int p;
cin >> p;
for (int i = 0; i < n; i++) {
a[i] -= p;
}
vector<int> pre = {a[0]};
for (int i = 1; i < n; i++) {
pre.push_back(pre.back() + a[i]);
}
vector<int> b = pre;
sort(b.begin(), b.end());
map<int, int> mp;
fenwick<int> fenw(n + 1);
for (int i = 0; i < n; i++) {
mp[pre[i]] = lower_bound(b.begin(), b.end(), pre[i]) - b.begin();
}
long long ans = 0ll;
for (int i = 0; i < n; i++) {
if (pre[i] >= 0) {
ans++;
}
ans += fenw.get(mp[pre[i]]);
fenw.modify(mp[pre[i]], +1);
}
cout << ans << endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
892 KB |
Output is correct |
2 |
Correct |
6 ms |
908 KB |
Output is correct |
3 |
Correct |
6 ms |
908 KB |
Output is correct |
4 |
Execution timed out |
1079 ms |
55440 KB |
Time limit exceeded |
5 |
Execution timed out |
1071 ms |
55440 KB |
Time limit exceeded |
6 |
Execution timed out |
1065 ms |
66560 KB |
Time limit exceeded |
7 |
Execution timed out |
1075 ms |
66560 KB |
Time limit exceeded |
8 |
Execution timed out |
1066 ms |
66560 KB |
Time limit exceeded |
9 |
Execution timed out |
1069 ms |
66560 KB |
Time limit exceeded |
10 |
Execution timed out |
1082 ms |
66560 KB |
Time limit exceeded |