This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr int inf = 1e9;
constexpr ll infl = 1e18;
struct Fenwick {
int n;
vector<int> tree;
Fenwick() = default;
Fenwick(int n) : n(n), tree(n) {}
int sum(int r) {
int s = 0;
for (; r >= 0; r = (r&(r+1))-1) s+= tree[r];
return s;
}
void inc(int i, int d=1) {
for (; i < n; i |= i+1) tree[i] += d;
}
};
int main() {
cin.tie(0)->sync_with_stdio(0);
int n;
cin >> n;
vector<int> arr(n);
for (int& i : arr) cin >> i;
set<int> poss(arr.begin(), arr.end());
ll cnt = 0;
for (int x : poss) {
vector<int> brr(n+1);
brr[0] = n;
for (int i = 0; i < n; i++){
brr[i+1] = brr[i] + (arr[i] == x ? 1 : -1);
}
Fenwick t(n*2+1);
t.inc(brr[0]);
for (int i = 1; i <= n; i++) {
cnt += t.sum(brr[i]-1);
t.inc(brr[i]);
}
}
cout << cnt << '\n';
}
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |