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답안 #734450

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
734450 2023-05-02T12:14:39 Z Abrar_Al_Samit 구슬과 끈 (APIO14_beads) C++17
0 / 100
 4 ms 6552 KB 
#include<bits/stdc++.h>
using namespace std;


const int nax = 200005;

vector<pair<int,int>>g[nax];

int dp[nax][2], n;

int solve(int v, int topar, int p = -1) {
	int &ret = dp[v][(topar>0)];
	if(ret!=-1) return ret;
	ret = 0;

	int base = 0;
	for(auto [u, w] : g[v]) if(u!=p) {
		base += solve(u, w, v);
	}

	ret = base;


	vector<int>lap;
	for(auto [u, w] : g[v]) if(u!=p) {
		lap.push_back(-solve(u, w, v) + solve(u, 0, v) + w);
	}
	sort(lap.rbegin(), lap.rend());

	for(int i=0, acc=0; i<min(2, (int)lap.size()); ++i) {
		acc += lap[i];
		if((~i&1) && topar) {
			ret = max(ret, base + acc + topar);
		} else if(i&1) {
			ret = max(ret, base + acc);
		}
	}
	return ret;
}
void PlayGround() {
	cin>>n;
	for(int i=1; i<n; ++i) {
		int u, v, w;
		cin>>u>>v>>w;
		g[u].emplace_back(v, w);
		g[v].emplace_back(u, w);
	}	

	memset(dp, -1, sizeof dp);
	cout<<solve(1, 0)<<'\n';

	// cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
}
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	PlayGround();
	return 0;
}

Subtask #1
0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 4 ms 6516 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 4 ms 6460 KB Output is correct
5 Correct 4 ms 6552 KB Output is correct
6 Incorrect 4 ms 6484 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #2
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 4 ms 6516 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 4 ms 6460 KB Output is correct
5 Correct 4 ms 6552 KB Output is correct
6 Incorrect 4 ms 6484 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 4 ms 6516 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 4 ms 6460 KB Output is correct
5 Correct 4 ms 6552 KB Output is correct
6 Incorrect 4 ms 6484 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 43.0

# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6484 KB Output is correct
2 Correct 4 ms 6516 KB Output is correct
3 Correct 3 ms 6484 KB Output is correct
4 Correct 4 ms 6460 KB Output is correct
5 Correct 4 ms 6552 KB Output is correct
6 Incorrect 4 ms 6484 KB Output isn't correct
7 Halted 0 ms 0 KB -