Submission #1017594

#	Time	Username	Problem	Language	Result	Execution time	Memory
1017594		vjudge1	Race (IOI11_race)	C++17	100 / 100	361 ms	107948 KiB

race

#include<bits/stdc++.h>
#include <cmath>
#include <complex>
#include<string>
#include <ext/pb_ds/assoc_container.hpp>
//#include "testlib.h"
//freopen("orxor.in", "r", stdin);
using namespace std;
using namespace __gnu_pbds;
template <class T>
using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define ll long long
#define pb push_back
#define F first
#define S second
#define fast ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define dcm(a) setprecision(a)<<fixed
ll const md=1e9+7;
double const EPS=1e-9;
int const LOG=22;
using uint = unsigned int;
using ull = unsigned long long;
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define clr(memo, a) memset(memo,a,sizeof(memo))
#define PI acos(-1)
#define endl '\n'
int const N=2e5+5;
vector<pair<int,ll> > adj[N];
int dep[N];
map<int,ll> mp[N];
ll sum[N];
ll ans=1e18;
ll k;
void dfs(int v,int p,int d,ll s)
{
    sum[v]=s;
    dep[v]=d;
    mp[v][s]=d;
    ll targ=k+2*s;
    for(auto[u,w]:adj[v]){
        if(u==p)
            continue;
        dfs(u,v,d+1,s+w);
        if(mp[u].size()>mp[v].size())
            swap(mp[u],mp[v]);
        for(auto[ss,dist]:mp[u]){
            if(mp[v].count(targ-ss)){
                ans=min(ans,mp[v][targ-ss]+dist-2*d);
            }
        }
        for(auto[ss,dist]:mp[u]){
            if(mp[v].count(ss)){
                mp[v][ss]=min(mp[v][ss],dist);
            }
            else{
                mp[v][ss]=dist;
            }
        }
    }
}
ll best_path(int n, int K, int edges[][2], int weights[]) {
	if (K == 1) { return 0ll; }
	k=K;
	ans = 1e18;
	for (int i = 0; i < n - 1; i++) {
		int u = edges[i][0];
		int v = edges[i][1];
		adj[u].push_back({v,weights[i]});
		adj[v].push_back({u,weights[i]});
	}
	dfs(0,-1,0,0);
	return ans == 1e18 ? -1ll : ans;
}
void solve(int testCase)
{
    int n;
    cin>>n;
    cin>>k;
    for(int i=0;i<n-1;i++){
        int x,y,w;
        cin>>x>>y>>w;
        adj[x].push_back({y,w});
        adj[y].push_back({x,w});
    }
    dfs(0,-1,0,0);
    cout<<ans<<endl;
}

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 22 / 22
• Subtask 4: 57 / 57