結果

問題 No.2604 Initial Motion
ユーザー Jeroen Op de BeekJeroen Op de Beek
提出日時 2024-01-12 22:00:38
言語 C++17(gcc12)
(gcc 12.3.0 + boost 1.87.0)
結果
AC  
実行時間 519 ms / 3,000 ms
コード長 3,841 bytes
コンパイル時間 2,219 ms
コンパイル使用メモリ 216,564 KB
実行使用メモリ 6,948 KB
最終ジャッジ日時 2024-09-27 22:11:46
合計ジャッジ時間 12,187 ms
ジャッジサーバーID
(参考情報)
judge3 / judge5
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 3
other AC * 39
権限があれば一括ダウンロードができます

ソースコード

diff #

#include "bits/stdc++.h"
using namespace std;
#define all(x) begin(x),end(x)
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { string sep; for (const T &x : v) os << sep << x, sep = " "; return os; }
#define debug(a) cerr << "(" << #a << ": " << a << ")\n";
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pi;
const int mxN = 1e4+1;
const ll oo = 3e18;
struct mincostflow {
    // Source is Node 0;
    // Sink is node n-1
    struct edge {
        ll f,c;
        int to;
        ll cost;
    };
    typedef vector<edge> ve;
    vector<vector<int>> adj;
    vector<edge> edges;
    int n;
    mincostflow(int _n) {
        n=_n;
        adj.resize(n);
        dist.resize(n);
        parent.resize(n);
        pflow.resize(n);
    }
    void addEdge(int a, int b, ll w, ll cost, bool directed = true) {
        adj[a].push_back((int)edges.size());
        adj[b].push_back((int)edges.size()+1);
        edges.push_back({0,w,b,cost});
        edges.push_back({0,directed?0:w,a,-cost});
    }
    bitset<mxN> inqueue;
    vector<ll> dist, pflow;
    vi parent;

    void SPFA() {
        fill(all(dist),oo);
        queue<int> q; q.push(0);
        parent[0] = -1;
        dist[0] = 0;
        inqueue[0]= true;
        pflow[0] = oo;
        while(!q.empty()) {
            int at = q.front(); q.pop();
            inqueue[at] = false;
            for(int ei: adj[at]) {
                auto& e = edges[ei];
                if(e.c-e.f<1) continue;
                ll constraint = min(e.c-e.f,pflow[at]);
                if(dist[at]+e.cost < dist[e.to]) {
                    parent[e.to] = ei;
                    pflow[e.to] = constraint;
                    dist[e.to] = dist[at]+e.cost;
                    if(!inqueue[e.to]) {
                        inqueue[e.to] = true;
                        q.push(e.to);
                    }
                } else if(dist[at]+e.cost==dist[e.to]) {
                    if(pflow[e.to]< constraint) {
                        parent[e.to] = ei;
                        pflow[e.to] = constraint;
                    }
                }
            }
        }

    }
    void findPath(ll extra) {
        int at = n-1;
        while(at!=0) {
            int ei = parent[at];
            auto& e = edges[ei];
            e.f+=extra;
            auto& o = edges[ei^1];
            o.f-=extra;
            at = o.to;
        }
    }
    pair<ll,ll> solve(int k) {
        ll flow = 0, cost = 0;
        while(true) {
            SPFA();
            if(dist[n-1]==oo)  {
                break;
            }
            int extraflow = pflow[n-1];
            ll shortestpath = dist[n-1];
            // debug(shortestpath);
            // debug(extraflow);
            if(flow+extraflow>=k) {
                cost+=shortestpath*(k-flow);
                flow = k;
                break;
            }
            flow+=extraflow;
            cost+=shortestpath*extraflow;
            findPath(pflow[n-1]);
            
        }
        return {flow,cost};
    }
};
int main() {
    int k,n,m; cin >> k >> n >> m;
    mincostflow mcf(n+2);
    for(int i=0;i<k;++i) {
        int a; cin >> a;
        mcf.addEdge(0,a,1,0);
    }
    for(int i=1;i<=n;++i) {
        int b; cin >> b;
        if(b) {
            mcf.addEdge(i,n+1,b,0);
        }
    }
    for(int i=0;i<m;++i) {
        ll w;
        int u,v; cin >> u >> v >> w;
        mcf.addEdge(u,v,1e9,w);
        mcf.addEdge(v,u,1e9,w);
    }
    auto [flow,res] = mcf.solve(1e9);
    cout << res << '\n';


}
0