제출 #42207

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
42207		Aidyn_A	구슬과 끈 (APIO14_beads)	C++14	0 / 100	7 ms	4992 KiB

beads

#include <stdio.h>
#include <bits/stdc++.h>			

#define pb push_back
#define pf push_front
#define pp pop_back
#define sz(a) (int)(a.size())
#define mp make_pair
#define F first
#define S second
#define next _next
#define prev _prev
#define left _left
#define right _right
#define y1 _y1
#define all(x) x.begin(), x.end()
#define what_is(x) #x << " is " << (x)

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int N = (int)1e5 + 123;
const ll INF = (ll)1e18 + 123;
const int inf = (int)1e9 + 123;
const int MOD = (int)1e9 + 7;

void megaRandom() {
	unsigned int FOR;
 	asm("rdtsc" : "=A"(FOR));
  srand(FOR);
}

int n;
vector<pii> g[N];
ll dp[3][N], res;

void dfs(int x, int pr = 0, int par_edge = 0) {
	ll sum = 0;
	for(auto to : g[x]) {
		if(to.F == pr) continue;
		dfs(to.F, x, to.S);
		sum += max(dp[0][to.F], dp[1][to.F]);
		dp[0][x] = max({dp[0][x], dp[1][to.F], dp[0][to.F]});
	}
	for(auto to : g[x]) {
		if(to.F == pr) continue;
		dp[1][x] = max(dp[1][x], dp[0][to.F] + to.S + par_edge + (sum - max(dp[0][to.F], dp[1][to.F])) );
	}
}

int main() {
	megaRandom();
	cin >> n;
	for(int i = 1, x, y, z; i < n; i ++) {
	 	cin >> x >> y >> z;
	 	g[x].pb(mp(y, z));
	 	g[y].pb(mp(x, z));
	}
	for(int root = 1; root <= n; root ++) {
	  memset(dp, 0, sizeof dp);
		dfs(root);
		res = max(res, dp[0][root]);
	}
	cout << res;
	return 0;  
}

• Subtask 1: 0 / 13
• Subtask 2: 0 / 15
• Subtask 3: 0 / 29
• Subtask 4: 0 / 43