#include<bits/stdc++.h>
#define f first
#define s second
#define ll long long
#define pii pair<int,int>
using namespace std;
const int N = 1e5 + 5, mod = 1e9 + 7; // !
int t, v[N], s[N], n;
ll dp[N], h[N];
vector<pii> V[N];
struct line {
int k, b;
};
vector<line> ts;
ll f(int k,int x,int b) {
return (ll)k * x + b;
}
double X_(line a, line b) {
// a.k * x + a.b = b.k * x + b.b
return (double)(b.b - a.b) / (a.k - b.k);
}
void dfs(int u,int p) {
// s[u] + (h[u] - h[p]) * v[u] + dp[p]
// -h[p] * v[u] + dp[p] + s[u] + h[u] * v[u]
vector<line> rem;
dp[u] = 0;
int l = 0, r = (int)ts.size() - 2;
if(ts.size()) dp[u] = min(dp[u], f(ts.back().k, v[u], ts.back().b));
while(l <= r) {
int mid = (l + r) / 2;
if(X_(ts[mid], ts[mid + 1]) <= v[u]) l = mid + 1, dp[u] = min(dp[u], f(ts[mid + 1].k, v[u], ts[mid + 1].b));
else r = mid - 1;
}
dp[u] += (ll) h[u] * v[u] + s[u];
line new_;
new_.k = -h[u]; new_.b = dp[u];
while(ts.size() >= 2) {
line cur = ts.back();
line prev = ts[(int)ts.size() - 2];
if(X_(cur, prev) >= X_(cur, new_)) rem.push_back(cur), ts.pop_back();
else break;
}
ts.push_back(new_);
for(int i = 0; i < V[u].size(); i++) {
if(V[u][i].f == p) continue;
h[V[u][i].f] = h[u] + V[u][i].s;
dfs(V[u][i].f, u);
}
ts.pop_back();
reverse(rem.begin(), rem.end());
for(int i = 0; i < rem.size(); i++) ts.push_back(rem[i]);
}
main(){
int n; cin >> n;
for(int i = 2; i <= n; i++) {
int u,v, w;
cin >> u >> v >> w;
V[u].push_back({v, w});
V[v].push_back({u, w});
}
for(int i = 2; i <= n; i++) {
int p;
cin >> s[i] >> v[i];
}
dfs(1, 0);
for(int i = 2; i <= n; i++) cout << dp[i] <<" ";
}
Compilation message
harbingers.cpp: In function 'void dfs(int, int)':
harbingers.cpp:45:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
45 | for(int i = 0; i < V[u].size(); i++) {
| ~~^~~~~~~~~~~~~
harbingers.cpp:52:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<line>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
52 | for(int i = 0; i < rem.size(); i++) ts.push_back(rem[i]);
| ~~^~~~~~~~~~~~
harbingers.cpp: At global scope:
harbingers.cpp:54:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
54 | main(){
| ^~~~
harbingers.cpp: In function 'int main()':
harbingers.cpp:63:7: warning: unused variable 'p' [-Wunused-variable]
63 | int p;
| ^
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
2636 KB |
Output is correct |
| 2 |
Correct |
5 ms |
3180 KB |
Output is correct |
| 3 |
Incorrect |
90 ms |
13048 KB |
Output isn't correct |
| 4 |
Incorrect |
113 ms |
17744 KB |
Output isn't correct |
| 5 |
Correct |
152 ms |
22724 KB |
Output is correct |
| 6 |
Correct |
181 ms |
27460 KB |
Output is correct |
| 7 |
Correct |
118 ms |
13384 KB |
Output is correct |
| 8 |
Execution timed out |
1047 ms |
17524 KB |
Time limit exceeded |
| 9 |
Execution timed out |
1049 ms |
15624 KB |
Time limit exceeded |
| 10 |
Execution timed out |
1043 ms |
19320 KB |
Time limit exceeded |
