#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define rnd(l, r) uniform_int_distribution<int>(l, r)(rng)
using namespace std;
void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int N = 1001, MX = 1e5 + 1;
int32_t tim[MX], cost[MX];
long long dp[MX], depth[N];
vector <int> g[MX];
int p[MX];
void dfs1(int v, int par){
p[v] = par;
for(auto to : g[v]){
if(to == par)continue;
depth[to] = depth[v] + 1;
dfs1(to, v);
}
}
void dfs(int v = 1, int time = 1){
int c = 0;
if(time == tim[v])c = cost[v];
dp[v] = max(dp[v], c * 1ll);
long long sum = 0;
for(auto to : g[v]){
if(to == p[v])continue;
sum += dp[to];
}
dp[v] = max(dp[v], sum + c);
if(v == 1)return;
dfs(p[v], time);
}
main(){
iostream::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n, m, k;
cin >> n >> m >> k;
for(int i = 2; i <= n; i++){
int a;
cin >> a;
g[a].pb(i);
g[i].pb(a);
}
dfs1(1, 1);
vector < array <int32_t, 3> > vp;
for(int i = 1 ; i<= m; i++){
int a, b, c;
cin >> a >> b >> c;
vp.pb({b, a, c});
}
sort(all(vp));
int cur = 0, prev = -1;
for(auto &[a, b, c] : vp){
if(a != prev)cur++;
prev = a;
a = cur;
swap(a, b);
}
for(auto &[a, b, c] : vp){
int x = b;
cost[a] = c;
tim[a] = b;
swap(b, c);
b = -depth[a];
c = x;
}
sort(all(vp));
for(auto &[a, b, c] : vp){
dfs(a, c);
}
cout <<dp[1] << endl;
}
/*
* Before implementing the problem:
Do I understand the problem correctly?
Which places are tricky? What do I need to remember to implement them correctly?
Which place is the heaviest by implementation? Can I do it simpler?
Which place is the slowest? Where do I need to be careful about constant factors and where I can choose slower but simpler implementation?
----------------------------------
If not AC:
Did you remember to do everything to handle the tricky places you thought about before?
Is the solution correct?
Do I understand the problem correctly?
----------------------------------
If you have a test on which the solution gives wrong answer:
Is the solution doing what it was supposed to do?
Is the problem in the code or in the idea?
*/
Compilation message
magictree.cpp:49:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
49 | main(){
| ^~~~
magictree.cpp: In function 'void fp(std::string)':
magictree.cpp:14:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
magictree.cpp:14:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
44 ms |
8476 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
4440 KB |
Output is correct |
| 2 |
Incorrect |
3 ms |
4696 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
93 ms |
9628 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
5208 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
