oj.uz

Submission #945768

# Submission time Handle Problem Language Result Execution time Memory
945768 2024-03-14T07:30:51 Z vjudge1 Magic Tree (CEOI19_magictree) C++17
6 / 100
 653 ms 1048576 KB 
#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 int long long
#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 long long N = 1005,  MX = 1e5 + 10;

long long cost[MX][N], dp[MX][N];
vector <int> g[MX];

void dfs(int v = 1, int par = 1, int time = 1){
	dp[v][time] = max(dp[v][time - 1], cost[v][time]);
	long long sum = 0;
	for(auto to : g[v]){
		if(to == par)continue;
		dfs(to, v, time);
		sum += dp[to][time];
		dp[v][time] = max(dp[v][time], dp[to][time] + cost[v][time]);
	}
	dp[v][time] = max(dp[v][time], sum + cost[v][time]);
}

main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
    long long 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);
	}
	vector < array <long long, 3 > > vp;
	for(int i = 1 ; i<= m; i++){
		long long a, b, c;
		cin >> a >> b >> c;
		vp.pb({b, a, c});
	}
	sort(all(vp));
	long long cur = -1, 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){
		cost[a][b] = c;
		swap(a, b);
	}
	for(int i = 0; i <= cur; i++){
		dfs(1, 1, i);
	}
	cout <<dp[1][cur] << 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:37:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   37 | main(){
      | ^~~~
magictree.cpp: In function 'void fp(std::string)':
magictree.cpp:15:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
magictree.cpp:15:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6748 KB Output is correct
2 Correct 1 ms 6744 KB Output is correct
3 Correct 2 ms 6748 KB Output is correct
4 Correct 1 ms 6748 KB Output is correct
5 Correct 1 ms 6796 KB Output is correct
6 Correct 3 ms 6748 KB Output is correct
7 Correct 3 ms 6748 KB Output is correct
8 Correct 2 ms 6768 KB Output is correct
9 Correct 2 ms 6904 KB Output is correct

Subtask #2
0 / 3.0

# Verdict Execution time Memory Grader output
1 Runtime error 235 ms 799652 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #3
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 20316 KB Output is correct
2 Correct 14 ms 20312 KB Output is correct
3 Correct 12 ms 20316 KB Output is correct
4 Runtime error 148 ms 801604 KB Execution killed with signal 11
5 Halted 0 ms 0 KB -

Subtask #4
0 / 12.0

# Verdict Execution time Memory Grader output
1 Runtime error 257 ms 1048576 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #5
0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6748 KB Output is correct
2 Correct 1 ms 6744 KB Output is correct
3 Correct 2 ms 6748 KB Output is correct
4 Correct 1 ms 6748 KB Output is correct
5 Correct 1 ms 6796 KB Output is correct
6 Correct 3 ms 6748 KB Output is correct
7 Correct 3 ms 6748 KB Output is correct
8 Correct 2 ms 6768 KB Output is correct
9 Correct 2 ms 6904 KB Output is correct
10 Runtime error 250 ms 1048576 KB Execution killed with signal 9
11 Halted 0 ms 0 KB -

Subtask #6
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 653 ms 320848 KB Output is correct
2 Runtime error 370 ms 1048576 KB Execution killed with signal 9
3 Halted 0 ms 0 KB -

Subtask #7
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6748 KB Output is correct
2 Correct 1 ms 6744 KB Output is correct
3 Correct 2 ms 6748 KB Output is correct
4 Correct 1 ms 6748 KB Output is correct
5 Correct 1 ms 6796 KB Output is correct
6 Correct 3 ms 6748 KB Output is correct
7 Correct 3 ms 6748 KB Output is correct
8 Correct 2 ms 6768 KB Output is correct
9 Correct 2 ms 6904 KB Output is correct
10 Correct 11 ms 20316 KB Output is correct
11 Correct 14 ms 20312 KB Output is correct
12 Correct 12 ms 20316 KB Output is correct
13 Runtime error 148 ms 801604 KB Execution killed with signal 11
14 Halted 0 ms 0 KB -

Subtask #8
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 6748 KB Output is correct
2 Correct 1 ms 6744 KB Output is correct
3 Correct 2 ms 6748 KB Output is correct
4 Correct 1 ms 6748 KB Output is correct
5 Correct 1 ms 6796 KB Output is correct
6 Correct 3 ms 6748 KB Output is correct
7 Correct 3 ms 6748 KB Output is correct
8 Correct 2 ms 6768 KB Output is correct
9 Correct 2 ms 6904 KB Output is correct
10 Runtime error 235 ms 799652 KB Execution killed with signal 11
11 Halted 0 ms 0 KB -