#include <bits/stdc++.h>
#define DEBUG 0
using namespace std;
const int MAX_N = 4e5 + 10;
int n, cnt;
int L[MAX_N], R[MAX_N];
int fenwick[MAX_N];
vector <int> arr[MAX_N];
int sz[MAX_N];
long long ans;
void update(const int &idx, const int &val) {
for(int i = idx; i < MAX_N; i += (i & -i)) {
fenwick[i] += val;
}
}
int query(const int &idx) {
int res = 0;
for(int i = idx; i >= 1; i -= (i & -i)) {
res += fenwick[i];
}
return res;
}
int read_input() {
int now;
cin >> now;
if(now == 0) {
now = ++cnt;
L[now] = read_input();
R[now] = read_input();
sz[now] = sz[L[now]] + sz[R[now]];
}
else {
now += n;
sz[now] = 1;
L[now] = R[now] = -1;
}
return now;
}
void dfs(const int &u, const bool &keep) {
if(L[u] == -1 and R[u] == -1) {
arr[u].push_back(u - n);
update(u - n, 1);
}
else {
int v1 = L[u], v2 = R[u];
if(sz[v1] < sz[v2]) {
swap(v1, v2);
}
dfs(v2, false);
dfs(v1, true);
long long inv = 0;
for(auto x : arr[v2]) {
inv += query(MAX_N - 1) - query(x);
}
swap(arr[u], arr[v1]);
for(auto x : arr[v2]) {
arr[u].push_back(x);
update(x, 1);
}
ans += min(inv, sz[v1] * sz[v2] - inv);
}
if(keep == false) {
for(auto x : arr[u]) {
update(x, -1);
}
}
}
int main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n;
read_input();
dfs(1, false);
cout << ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
9684 KB |
Output is correct |
2 |
Correct |
6 ms |
9728 KB |
Output is correct |
3 |
Correct |
6 ms |
9684 KB |
Output is correct |
4 |
Correct |
5 ms |
9684 KB |
Output is correct |
5 |
Correct |
5 ms |
9732 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
9776 KB |
Output is correct |
2 |
Correct |
5 ms |
9732 KB |
Output is correct |
3 |
Correct |
5 ms |
9756 KB |
Output is correct |
4 |
Correct |
5 ms |
9732 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
9812 KB |
Output is correct |
2 |
Correct |
6 ms |
9836 KB |
Output is correct |
3 |
Correct |
6 ms |
9812 KB |
Output is correct |
4 |
Correct |
6 ms |
9812 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
10332 KB |
Output is correct |
2 |
Correct |
8 ms |
10068 KB |
Output is correct |
3 |
Correct |
7 ms |
10452 KB |
Output is correct |
4 |
Correct |
8 ms |
10452 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
10 ms |
11860 KB |
Output is correct |
2 |
Correct |
14 ms |
10900 KB |
Output is correct |
3 |
Correct |
33 ms |
12748 KB |
Output is correct |
4 |
Correct |
12 ms |
11668 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
47 ms |
14184 KB |
Output is correct |
2 |
Correct |
32 ms |
15992 KB |
Output is correct |
3 |
Correct |
40 ms |
18340 KB |
Output is correct |
4 |
Correct |
35 ms |
18208 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
45 ms |
24960 KB |
Output is correct |
2 |
Correct |
50 ms |
21896 KB |
Output is correct |
3 |
Correct |
69 ms |
19468 KB |
Output is correct |
4 |
Correct |
45 ms |
17544 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
69 ms |
18488 KB |
Output is correct |
2 |
Correct |
68 ms |
21364 KB |
Output is correct |
3 |
Incorrect |
67 ms |
26552 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
179 ms |
29912 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
124 ms |
25412 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
158 ms |
25804 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |