#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int N;
cin >> N;
vector<int> A(N), H(N), C(N);
for (int i = 0; i < N; i++) {
cin >> A[i] >> H[i] >> C[i];
A[i]--;
}
{ // Coordinate Compression
vector<int> coords;
for (int i = 0; i < N; i++) {
coords.emplace_back(H[i]);
}
sort(begin(coords), end(coords));
coords.resize(unique(begin(coords), end(coords)) - begin(coords));
for (int i = 0; i < N; i++) {
H[i] = lower_bound(begin(coords), end(coords), H[i]) - begin(coords);
}
}
const auto Solve = [&](vector<int> component) -> long long {
// Cycle + Tree graph
// Cycle = super root, has many possible costs, try all of them
//
// Solve for tree:
// dp[u][x] = minimum cost when H[u] >= x
// diff[u][x] = dp[u][x] - dp[u][x - 1]
//
// Note:
// dp[u][x] <= dp[u][x + 1], since dp[u][x] = min(dp[u][x], dp[u][x + 1])
// 0 <= diff[x + 1]
//
// Case 1: Don't change H[u]
// dp[u][x] = sum(dp[v][H[u]]), for x <= H[u]
//
// Case 2: Change H[u]
// dp[u][x] = C[u] + sum(dp[v][x])
static vector<int> vis(N);
static vector<int> outdeg(N);
for (auto u : component) outdeg[A[u]] += 1;
vector<int> tree;
for (auto u : component) if (outdeg[u] == 0) {
vis[u] = 1;
tree.emplace_back(u);
}
for (int i = 0; i < int(tree.size()); i++) {
int u = tree[i];
outdeg[A[u]]--;
if (outdeg[A[u]] == 0) {
vis[A[u]] = 1;
tree.emplace_back(A[u]);
}
}
long long sum_cost_cycle = 0;
map<int, int> value_sum_cost;
value_sum_cost[0] = 0;
for (auto u : component) {
if (!vis[u]) {
sum_cost_cycle += C[u];
value_sum_cost[H[u]] += C[u];
}
}
// For x > H[u]: dp[u][x] = C[u] + sum(dp[v][x])
// diff[H[u] + 1] += C[u]
//
// For x <= H[u]: dp[u][x] = min(C[u] + sum(dp[v][x]), sum(dp[v][H[u]]))
// Let x be greatest, s.t. sum(dp[v][x]) + C[u] < sum(dp[v][H[u]]):
// Then C[u] < sum_{x < y <= H[u]}(diff[y])
// But for all x + 1 <= y <= H[u]; diff[y] changes to 0.
// We can iterate for all y, backwards
//
// diff[x + 1] = sum(dp[v][H[u]]) - sum(dp[v][x]) - C[u]
// diff[x + 1] = sum_{x < y <= H[u]}(diff[y]) - C[u]
// diff[0] += C[u]
static vector<map<int, long long>> diff(N + 1);
diff[N].clear();
for (auto u : tree) {
if (!vis[A[u]]) A[u] = N;
diff[u][H[u] + 1] += C[u];
long long diffsum = 0;
while (diff[u].find(H[u] + 1) != begin(diff[u])) {
auto d = *prev(diff[u].find(H[u] + 1));
diff[u].erase(diff[u].find(d.first));
diffsum += d.second;
if (C[u] < diffsum) {
diff[u][d.first] += diffsum - C[u];
diff[u][0] += C[u];
diffsum = -1;
break;
}
}
if (diffsum != -1) {
diff[u][0] += diffsum;
}
// Propagate to parent
if (diff[A[u]].size() < diff[u].size()) {
swap(diff[A[u]], diff[u]);
}
for (auto d : diff[u]) {
diff[A[u]][d.first] += d.second;
}
}
map<int, long long> dp;
for (auto [h, sub] : value_sum_cost) {
dp[h] = 0;
}
for (auto [h, d] : diff[N]) {
dp[h] = 0;
}
long long sum = 0;
for (auto [h, v] : dp) {
sum += diff[N][h];
dp[h] = sum;
}
long long ans = 1e18;
for (auto [h, sub] : value_sum_cost) {
ans = min(ans, sum_cost_cycle - sub + dp[h]);
}
return ans;
};
long long ans = 0;
// Solve for each connected component
vector<vector<int>> adj(N);
for (int i = 0; i < N; i++) {
adj[A[i]].emplace_back(i);
adj[i].emplace_back(A[i]);
}
vector<int> done(N);
for (int i = 0; i < N; i++) if (!done[i]) {
done[i] = 1;
vector<int> que = {i};
for (int q = 0; q < int(que.size()); q++) {
int u = que[q];
for (auto v : adj[u]) if (!done[v]) {
done[v] = 1;
que.emplace_back(v);
}
}
ans += Solve(que);
}
cout << ans << '\n';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
1 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
320 KB |
Output is correct |
5 |
Correct |
11 ms |
2640 KB |
Output is correct |
6 |
Correct |
9 ms |
1868 KB |
Output is correct |
7 |
Correct |
6 ms |
1640 KB |
Output is correct |
8 |
Correct |
10 ms |
2668 KB |
Output is correct |
9 |
Correct |
7 ms |
1864 KB |
Output is correct |
10 |
Correct |
6 ms |
1612 KB |
Output is correct |
11 |
Correct |
4 ms |
1384 KB |
Output is correct |
12 |
Correct |
7 ms |
1092 KB |
Output is correct |
13 |
Correct |
5 ms |
1100 KB |
Output is correct |
14 |
Correct |
7 ms |
1100 KB |
Output is correct |
15 |
Correct |
6 ms |
1100 KB |
Output is correct |
16 |
Correct |
10 ms |
2764 KB |
Output is correct |
17 |
Correct |
7 ms |
1996 KB |
Output is correct |
18 |
Correct |
4 ms |
1356 KB |
Output is correct |
19 |
Correct |
8 ms |
1732 KB |
Output is correct |
20 |
Correct |
5 ms |
1356 KB |
Output is correct |
21 |
Correct |
6 ms |
1356 KB |
Output is correct |
22 |
Correct |
8 ms |
2380 KB |
Output is correct |
23 |
Correct |
5 ms |
1740 KB |
Output is correct |
24 |
Correct |
9 ms |
1772 KB |
Output is correct |
25 |
Correct |
5 ms |
1396 KB |
Output is correct |
26 |
Correct |
6 ms |
1100 KB |
Output is correct |
27 |
Correct |
8 ms |
1996 KB |
Output is correct |
28 |
Correct |
9 ms |
1740 KB |
Output is correct |
29 |
Correct |
8 ms |
1740 KB |
Output is correct |
30 |
Correct |
9 ms |
1868 KB |
Output is correct |
31 |
Correct |
8 ms |
1876 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
2676 KB |
Output is correct |
2 |
Correct |
708 ms |
112768 KB |
Output is correct |
3 |
Correct |
522 ms |
72772 KB |
Output is correct |
4 |
Correct |
715 ms |
112356 KB |
Output is correct |
5 |
Correct |
503 ms |
72620 KB |
Output is correct |
6 |
Correct |
341 ms |
46536 KB |
Output is correct |
7 |
Correct |
279 ms |
40912 KB |
Output is correct |
8 |
Correct |
312 ms |
29488 KB |
Output is correct |
9 |
Correct |
285 ms |
29352 KB |
Output is correct |
10 |
Correct |
144 ms |
29356 KB |
Output is correct |
11 |
Correct |
310 ms |
29356 KB |
Output is correct |
12 |
Correct |
264 ms |
29384 KB |
Output is correct |
13 |
Correct |
600 ms |
123160 KB |
Output is correct |
14 |
Correct |
382 ms |
78628 KB |
Output is correct |
15 |
Correct |
161 ms |
40748 KB |
Output is correct |
16 |
Correct |
454 ms |
54740 KB |
Output is correct |
17 |
Correct |
217 ms |
40808 KB |
Output is correct |
18 |
Correct |
153 ms |
40748 KB |
Output is correct |
19 |
Correct |
598 ms |
79104 KB |
Output is correct |
20 |
Correct |
189 ms |
54136 KB |
Output is correct |
21 |
Correct |
523 ms |
55512 KB |
Output is correct |
22 |
Correct |
235 ms |
41196 KB |
Output is correct |
23 |
Correct |
152 ms |
29388 KB |
Output is correct |
24 |
Correct |
422 ms |
62008 KB |
Output is correct |
25 |
Correct |
358 ms |
54384 KB |
Output is correct |
26 |
Correct |
360 ms |
53296 KB |
Output is correct |
27 |
Correct |
489 ms |
59452 KB |
Output is correct |
28 |
Correct |
521 ms |
59472 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
1 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
320 KB |
Output is correct |
5 |
Correct |
11 ms |
2640 KB |
Output is correct |
6 |
Correct |
9 ms |
1868 KB |
Output is correct |
7 |
Correct |
6 ms |
1640 KB |
Output is correct |
8 |
Correct |
10 ms |
2668 KB |
Output is correct |
9 |
Correct |
7 ms |
1864 KB |
Output is correct |
10 |
Correct |
6 ms |
1612 KB |
Output is correct |
11 |
Correct |
4 ms |
1384 KB |
Output is correct |
12 |
Correct |
7 ms |
1092 KB |
Output is correct |
13 |
Correct |
5 ms |
1100 KB |
Output is correct |
14 |
Correct |
7 ms |
1100 KB |
Output is correct |
15 |
Correct |
6 ms |
1100 KB |
Output is correct |
16 |
Correct |
10 ms |
2764 KB |
Output is correct |
17 |
Correct |
7 ms |
1996 KB |
Output is correct |
18 |
Correct |
4 ms |
1356 KB |
Output is correct |
19 |
Correct |
8 ms |
1732 KB |
Output is correct |
20 |
Correct |
5 ms |
1356 KB |
Output is correct |
21 |
Correct |
6 ms |
1356 KB |
Output is correct |
22 |
Correct |
8 ms |
2380 KB |
Output is correct |
23 |
Correct |
5 ms |
1740 KB |
Output is correct |
24 |
Correct |
9 ms |
1772 KB |
Output is correct |
25 |
Correct |
5 ms |
1396 KB |
Output is correct |
26 |
Correct |
6 ms |
1100 KB |
Output is correct |
27 |
Correct |
8 ms |
1996 KB |
Output is correct |
28 |
Correct |
9 ms |
1740 KB |
Output is correct |
29 |
Correct |
8 ms |
1740 KB |
Output is correct |
30 |
Correct |
9 ms |
1868 KB |
Output is correct |
31 |
Correct |
8 ms |
1876 KB |
Output is correct |
32 |
Correct |
11 ms |
2676 KB |
Output is correct |
33 |
Correct |
708 ms |
112768 KB |
Output is correct |
34 |
Correct |
522 ms |
72772 KB |
Output is correct |
35 |
Correct |
715 ms |
112356 KB |
Output is correct |
36 |
Correct |
503 ms |
72620 KB |
Output is correct |
37 |
Correct |
341 ms |
46536 KB |
Output is correct |
38 |
Correct |
279 ms |
40912 KB |
Output is correct |
39 |
Correct |
312 ms |
29488 KB |
Output is correct |
40 |
Correct |
285 ms |
29352 KB |
Output is correct |
41 |
Correct |
144 ms |
29356 KB |
Output is correct |
42 |
Correct |
310 ms |
29356 KB |
Output is correct |
43 |
Correct |
264 ms |
29384 KB |
Output is correct |
44 |
Correct |
600 ms |
123160 KB |
Output is correct |
45 |
Correct |
382 ms |
78628 KB |
Output is correct |
46 |
Correct |
161 ms |
40748 KB |
Output is correct |
47 |
Correct |
454 ms |
54740 KB |
Output is correct |
48 |
Correct |
217 ms |
40808 KB |
Output is correct |
49 |
Correct |
153 ms |
40748 KB |
Output is correct |
50 |
Correct |
598 ms |
79104 KB |
Output is correct |
51 |
Correct |
189 ms |
54136 KB |
Output is correct |
52 |
Correct |
523 ms |
55512 KB |
Output is correct |
53 |
Correct |
235 ms |
41196 KB |
Output is correct |
54 |
Correct |
152 ms |
29388 KB |
Output is correct |
55 |
Correct |
422 ms |
62008 KB |
Output is correct |
56 |
Correct |
358 ms |
54384 KB |
Output is correct |
57 |
Correct |
360 ms |
53296 KB |
Output is correct |
58 |
Correct |
489 ms |
59452 KB |
Output is correct |
59 |
Correct |
521 ms |
59472 KB |
Output is correct |
60 |
Correct |
1 ms |
320 KB |
Output is correct |
61 |
Correct |
1 ms |
320 KB |
Output is correct |
62 |
Correct |
1 ms |
204 KB |
Output is correct |
63 |
Correct |
1 ms |
204 KB |
Output is correct |
64 |
Correct |
702 ms |
80540 KB |
Output is correct |
65 |
Correct |
472 ms |
53276 KB |
Output is correct |
66 |
Correct |
634 ms |
74664 KB |
Output is correct |
67 |
Correct |
526 ms |
55724 KB |
Output is correct |
68 |
Incorrect |
343 ms |
39496 KB |
Output isn't correct |
69 |
Halted |
0 ms |
0 KB |
- |