Submission #1255383

#	Time	Username	Problem	Language	Result	Execution time	Memory
1255383		thdh__	Designated Cities (JOI19_designated_cities)	C++20	16 / 100	303 ms	55668 KiB

designated_cities

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define eb emplace_back
#define pu push
#define ins insert
#define fi first
#define se second
#define all(a) a.begin(),a.end()
#define bruh ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fu(x,a,b) for (auto x=a;x<=b;x++)
#define fd(x,a,b) for (auto x=a;x>=b;x--)
#define int ll

using namespace std;
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());

/*
Competitive Programming notes that I need to study & fix my dumbass self:

1. Coding:
- Always be sure to check the memory of arrays (maybe use vectors), for loops
- Always try to maximize the memory if possible, even if you are going for subtasks
- Do not exploit #define int long long, it will kill you

2. Stress: 
- Always try generating big testcases and try if they run

3. Time management:
- Don't overcommit or undercommit, always spend a certain amount of time to think a problem, don't just look at it and say I'm fucked
- Do not spend too much time coding brute-force solutions, they should be easily-codable solutions that don't take up too much time

Time management schedule:
Offline / LAH days (4 problems - 3h):
15' thinking of solution / idea
1. no idea: skip
2. yes idea: continue thinking for <= 15'

+ implementing: <= 20'
+ brute-force: <= 5'
+ test generator: <= 5'

I hate offline because I am dumb
*/

typedef pair<int, int> ii;
const int N = 2e5+5;
const int B = 750;
const int mod = 1e9+7;
const int inf = 1e18;
using cd = complex<double>;
const long double PI = acos(-1);
int power(int a,int b) {ll x = 1;if (a >= mod) a%=mod; while (b) {if (b & 1) x = x*a % mod;a = a*a % mod;b>>=1;}return x;} 

int n,q;
vector<pair<int, ii>> adj[N];
int ans[N], sum = 0, mn = inf, add = inf, root = 1;

int dfs(int u, int p, int cur) 
{
	int mx1 = -inf, mx2 = -inf;
	for (auto i : adj[u]) 
	{
		int v = i.fi, a = i.se.fi, b = i.se.se;
		if (v == p) continue;
		sum += a;
		int tmp = dfs(v, u, cur+b-a) + a;
		if (mx1 < tmp) mx2 = mx1, mx1 = tmp;
		else if (mx2 < tmp) mx2 = tmp;
	}
	add = min(add, cur);
	if (mn > cur-mx1-mx2 && adj[u].size() != 1) 
	{
		root = u;
		mn = cur-mx1-mx2;
	}
	return max(mx1, 0ll);
}

vector<int> delta[N];
int best[N];

void dfs1(int u, int p) 
{
	int mxsz = 0;
	int id = -1, id1 = -1, id2 = -1, mx1 = -inf, mx2 = -inf;
	for (auto i : adj[u]) 
	{
		int v = i.fi, a = i.se.fi, b = i.se.se;
		if (v == p) continue;
		sum += a;
		dfs1(v, u);
		best[v] += a;
		if (delta[v].size() > mxsz) mxsz = delta[v].size(), id = v;
		if (best[v] > best[u]) 
		{
			id2 = id1, mx2 = mx1;
			mx1 = best[v], id1 = v;
			best[u] = mx1;
		} else if (best[v] > mx2) 
		{
			mx2 = best[v], id2 = v;
		}
	}
	if (id != -1) swap(delta[u], delta[id]);
	for (auto i : adj[u]) 
	{
		int v = i.fi, a = i.se.fi, b = i.se.se;
		if (v == p) continue;
		if (v != id) 
		{
			for (auto j : delta[v]) delta[u].pb(j);
		}
		if (v != id1 && (p != -1 || v != id2)) delta[u].pb(best[v]);
	}
	if (!p && id2 != -1) best[u] += mx2;
}

void solve()
{
	cin>>n;
	for (int i = 1; i < n; i++) 
	{
		int u,v,a,b;
		cin>>u>>v>>a>>b;
		adj[u].pb({v,{a,b}}); adj[v].pb({u,{b,a}});
	}
	for (int i = 1; i <= n; i++) if (adj[i].size() > 1) {root = i; break;}
	dfs(root, 0, 0);
	ans[1] = sum + add;
	sum = 0;
	dfs1(root, 0);
	ans[2] = sum - best[root];
	sort(all(delta[root]));
	for (int i = 3; i <= n; i++) 
	{
		if (!delta[root].size()) ans[i] = ans[i-1];
		else 
		{
			ans[i] = ans[i-1] - delta[root].back();
			delta[root].pop_back();
		}
	}
	cin>>q;
	while (q--) 
	{
		int x; cin>>x;
		cout<<ans[x]<<endl;
	}
}

/*
Go through the mistakes you usually make and revise your code, for god's sake...
*/

signed main()
{
	bruh
	//freopen("input.inp","r",stdin);
	//freopen("output.inp","w",stdout);
	int t = 1;
	// cin>>t;
	while (t--)
	{
		solve();
		cout<<"\n";
	}
}

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