Submission #799683

#	Time	Username	Problem	Language	Result	Execution time	Memory
799683		vjudge1	Putovanje (COCI20_putovanje)	C++17	25 / 110	552 ms	95204 KiB

putovanje

#include <bits/stdc++.h>

using namespace std;

#define endl "\n"
#define int long long
#define all(x) (x).begin(), (x).end()
#define debug(x) cout << #x << ": " << x << endl
#define pb push_back
#define eb emplace_back
#define vi vector<int>
#define rep(i,a,b) for(int i=(int)(a); i < (int)(b); i++)

typedef long long ll;

using iiii = array<int, 4>;

const int oo = 0x3f3f3f3f3f3f3f3f;
const int MAXN = 2e5+2;

vector<vector<int>> g(MAXN);
map<pair<int,int>, int> cost_each, cost_free;
vector<int> tin(2*MAXN), tout(2*MAXN);
vector<vector<int>> up(MAXN, vector<int>(20));
int TIMER = 0;
vector<int> ans(MAXN, 0);
vector<int> cost_each_vertex(MAXN), cost_free_vertex(MAXN);
int res = 0;

void dfs(int u=0, int p=0) {
	tin[u] = TIMER++;

	cost_each_vertex[u] = cost_each[{u, p}];
	cost_free_vertex[u] = cost_free[{u, p}];

	up[u][0] = p;
	for(int i = 1; i < 20; i++)
		up[u][i] = up[up[u][i-1]][i-1];
	
	for(auto v: g[u]) if(v != p)
		dfs(v, u);

	tout[u] = TIMER++;

	/*
	cout << "---------- db -----------\n";
	cout << "u = " << u << endl;
	cout << "tin[u] = " << tin[u] << endl;
	cout << "set " << query(tin[u], tin[u]) << endl;
	cout << "tout[u] = " << tout[u] << endl;
	cout << "set " << query(tout[u], tout[u]) << endl;
	*/
}

int is_ancestor(int u, int v) {
	return tin[u] <= tin[v] && tout[u] >= tout[v];
}

int lca(int u, int v) {
	
	if(is_ancestor(u, v)) {
		ans[u]--;
		ans[v]++;
		return u;
	}

	if(is_ancestor(v, u)) {
		ans[v]--;
		ans[u]++;
		return v;
	}

	ans[u]++;
	ans[v]++;
	for(int i = 19; i >= 0; i--) {
		if(!is_ancestor(up[u][i], v))
			u = up[u][i];
	}
	ans[up[u][0]]--;
	return up[u][0];
}

void compute_ans(int u=1, int p=0) {
	for(auto v: g[u]) if(v != p) {
		compute_ans(v, u);
		ans[u] += ans[v];
	}
	res += min(ans[u]*cost_each_vertex[u], cost_free_vertex[u]);
}

void solve() {
	int n;
	cin >> n;
	vector<iiii> edges(n-1);

	for(auto& [a, b, c, d]: edges) {
		cin >> a >> b >> c >> d;
		g[a].push_back(b);
		g[b].push_back(a);
		cost_each[{a, b}] = c;
		cost_each[{b, a}] = c;
		cost_free[{a, b}] = d;
		cost_free[{b, a}] = d;
	}

	g[0].push_back(1);
	dfs();

	for(int i = 1; i+1 <= n; i++) {
		lca(i, i+1);
	}
	compute_ans();
	cout << res << '\n';
}

int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int t = 1;
    // cin >> t;
    while(t--) solve();
    return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 25 / 25
• Subtask 3: 0 / 65