#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define ll long long
const int N = 1e6+5 , INF = 1e9 , MOD = 1e9+7;
vector<ll> fenwick(N),a(N);
void update(ll node , ll val){
for(ll i = node; i < N; i += (i & -i)){
fenwick[i] += val;
}
}
ll query(ll node){
ll ans = 0;
for(ll i = node; i >= 1; i -= (i & -i)){
ans += fenwick[i];
}
return ans;
}
void solve(){
ll n;
cin >> n;
for(ll i = 1; i <= n; i++) cin >> a[i];
ll p;
cin >> p;
ll sum = 0;
vector<pair<ll,ll>> val;
val.push_back(make_pair(0,0));
for(int i = 1; i <= n; i++){
sum += a[i];
val.push_back(make_pair(sum-p*i,i));
}
sort(val.begin(),val.end());
vector<ll> cc(n+5);
ll cnt = 0;
for(ll i = 0; i < n+1; i++){
if(i != 0 && val[i].first == val[i-1].first){
cc[val[i].second] = cnt;
}
else{
cnt++;
cc[val[i].second] = cnt;
}
}
update(cc[0],1);
ll ans = 0;
for(int i = 1; i <= n; i++){
ans += query(cc[i]);
update(cc[i],1);
}
cout << ans;
}
int main(){
fast;
ll tc = 1;
// cin >> tc;
while(tc--) solve();
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
16156 KB |
Output is correct |
2 |
Correct |
8 ms |
16212 KB |
Output is correct |
3 |
Correct |
8 ms |
16164 KB |
Output is correct |
4 |
Correct |
231 ms |
43040 KB |
Output is correct |
5 |
Correct |
131 ms |
36992 KB |
Output is correct |
6 |
Correct |
203 ms |
40520 KB |
Output is correct |
7 |
Correct |
205 ms |
41364 KB |
Output is correct |
8 |
Correct |
176 ms |
38584 KB |
Output is correct |
9 |
Correct |
227 ms |
43792 KB |
Output is correct |
10 |
Correct |
203 ms |
40744 KB |
Output is correct |