Submission #105283

#	Time	Username	Problem	Language	Result	Execution time	Memory
105283		antimirage	Designated Cities (JOI19_designated_cities)	C++14	0 / 100	4 ms	512 KiB

designated_cities

#include <bits/stdc++.h>
 
#define fr first
#define sc second
#define mk make_pair
#define pb push_back
#define all(s) s.begin(), s.end()
 
using namespace std;
 
const int N = 2e5 + 5;

int n, q, x, y, c, d, cnt;

long long ans, pref[N], res, ALL;

vector < vector < pair <int, pair <int, int> > > > g;
 
void dfs (int v, int p = 0, long long cur = 0)
{	
	if (g[v].size() == 1 && p)
		cnt++;
		
	for (auto to : g[v]){
		
		if (to.fr == p) continue;
		
		dfs(to.fr, v, cur + to.sc.fr - to.sc.sc);
		
		pref[v] = max( pref[v], pref[to.fr] + to.sc.fr);
		ans += to.sc.sc;
		
		ALL += to.sc.fr;
		ALL += to.sc.sc;
	}
	vector <long long> vec;
	
	for (auto to : g[v]){
		if (to.fr == p) continue;
		vec.pb( pref[to.fr] + to.sc.fr);
	}
	sort(all(vec));
	reverse(all(vec));
	
	if (vec.size() > 1)
		res = max(res, vec[0] + vec[1] + cur);
}
main(){
	
	cin >> n;
	g.resize(n + 1);
	
	for (int i = 1; i < n; i++){
		scanf("%d%d%d%d", &x, &y, &c, &d);
		g[x].pb( mk( y, mk(c, d) ) );	
		g[y].pb( mk( x, mk(d, c) ) );	
	}
	dfs(1);
	
	cin >> q;
	while (q--){
		cin >> x;
		assert(x == 2);
		
		if(cnt == 2)
			puts("0");
		else
			cout << ALL - res - ans << endl;
	}
}
/**
4
1 2 1 2
1 3 3 4
1 4 5 6
**/

Compilation message (stderr)

designated_cities.cpp:48:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^
designated_cities.cpp: In function 'int main()':
designated_cities.cpp:54:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d%d", &x, &y, &c, &d);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 9
• Subtask 4: 0 / 17
• Subtask 5: 0 / 17
• Subtask 6: 0 / 44