Submission #928176

#	Time	Username	Problem	Language	Result	Execution time	Memory
928176		Darren0724	Designated Cities (JOI19_designated_cities)	C++17	7 / 100	157 ms	31248 KiB

designated_cities

#include <bits/stdc++.h>
using namespace std;
#define LCBorz ios_base::sync_with_stdio(false); cin.tie(0);
#define int long long
#define all(x) x.begin(), x.end()
#define endl '\n'
const int N=200005;
const int INF=1e18;
int n;
vector<pair<int,int>> adj[N];
vector<int> v(N);
void dfs1(int k,int pa){
    for(auto [j,c]:adj[k]){
        if(j==pa)continue;
        v[1]+=c;
        dfs1(j,k);
    }
} 
void dfs2(int k,int pa,int now){
    for(auto [j,c]:adj[k]){
        if(j==pa){
            v[k]=now+c;
        }
    }
    for(auto [j,c]:adj[k]){
        if(j==pa){
            continue;
        }
        dfs2(j,k,v[k]-c);
    }
}
int32_t main() {
    LCBorz;
    int n;cin>>n;
    int total=0;
    for(int i=1;i<n;i++){
        int a,b,c,d;cin>>a>>b>>c>>d;
        adj[a].push_back({b,d});
        adj[b].push_back({a,c});
        total+=c+d;
    }
    dfs1(1,1);
    dfs2(1,1,v[1]);
    int mx=*max_element(all(v));
    cout<<total-mx<<endl;
    

    return 0;
}

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