Dijkstra模版(LRJ)

#include<cstdio>
#include<cstring>
#include<queue>
#include<algorithm>
using namespace std;

const int INF = 1000000000;
const int maxn = 4000 + 10;

struct Edge {
  int from, to, dist, val;
};

struct HeapNode {
  int d, u;
  bool operator < (const HeapNode& rhs) const {
    return d > rhs.d;
  }
};

struct Dijkstra {
  int n, m;
  vector<Edge> edges;
  vector<int> G[maxn];
  bool done[maxn];    // 是否已永久标号
  int d[maxn];        // s到各个点的距离
  int p[maxn];        // 最短路中的上一条弧

  void init(int n) {
    this->n = n;
    for(int i = 0; i < n; i++) G[i].clear();
    edges.clear();
  }

  void AddEdge(int from, int to, int dist, int val) {
    edges.push_back((Edge){from, to, dist, val});
    m = edges.size();
    G[from].push_back(m-1);
  }

  void dijkstra(int s) {
    priority_queue<HeapNode> Q;
    for(int i = 0; i < n; i++) d[i] = INF;
    d[s] = 0;
    memset(done, 0, sizeof(done));
    Q.push((HeapNode){0, s});
    while(!Q.empty()) {
      HeapNode x = Q.top(); Q.pop();
      int u = x.u;
      if(done[u]) continue;
      done[u] = true;
      for(int i = 0; i < G[u].size(); i++) {
        Edge& e = edges[G[u][i]];
        if(d[e.to] > d[u] + e.dist) {
          d[e.to] = d[u] + e.dist;
          p[e.to] = G[u][i];
          Q.push((HeapNode){d[e.to], e.to});
        }
      }
    }
  }

  vector<int> GetShortestPath(int s, int t) {
    vector<int> path;
    while(t != s) {
      path.push_back(edges[p[t]].val);
      t = edges[p[t]].from;
    }
    reverse(path.begin(), path.end());
    return path;
  }
};

时间复杂度O((m + n)log n),
 图中节点编号得从0开始,邻接表储存,所以不用判重,如果是无向图,每条无向边需调用两次AddEdge

#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
#include <algorithm>
#include <map>
#include <vector>
#include<queue>
using namespace std;
typedef long long LL;
typedef pair<int,int> P;
const int maxn = 10000 + 5;
const int INF = 1000000000;

struct Edge{
    int from,to,dis;
    Edge(int from,int to,int dis){
        this -> from = from;
        this -> to = to;
        this -> dis = dis;
    }
};

int d[maxn];
int vis[maxn];
vector<Edge> G[maxn];

void Dij(int x,int n){
    priority_queue<P,vector<P>,greater<P> > Q;
    memset(vis,0,sizeof(vis));
    for(int i = 0;i <= n;i++) d[i] = INF;
    Q.push(P(0,x));
    while(!Q.empty()){
        P p = Q.top();Q.pop();
        int id = p.second;
        int dis = p.first;
        if(vis[id] == 1) continue;
        vis[id] = 1;
        d[id] = dis;
        for(int i = 0;i < G[id].size();i++){
            Edge edgs = G[id][i];
            int to = edgs.to;
            int der = edgs.dis;
            if(d[to] > d[id] + der){
                d[to] = d[id] + der;
                Q.push(P(d[to],to));
            }
        }
    }
}


int main(){
    int t,kase = 0;
    scanf("%d",&t);
    while(t--){
        int n,m;
        kase++;
        for(int i = 0;i < maxn;i++) G[i].clear();
        scanf("%d%d",&n,&m);
        for(int i = 1;i <= n;i++){
            int x;scanf("%d",&x);
            G[0].push_back(Edge(0,i,x));
        }
        while(m--){
            int a,b,c1,c2;
            scanf("%d%d%d%d",&a,&b,&c1,&c2);a++;b++;
            G[a].push_back(Edge(a,b,c1));
            G[b].push_back(Edge(b,a,c2));
        }
        Dij(0,n);
        int ans = 0,ansx;
        for(int i = 1;i <= n;i++){
            if(d[i] > ans){
                ans = d[i];
                ansx = i-1;
            }
        }
        printf("Scenario #%d:\n",kase);
        printf("%d\n",ansx);
        printf("\n");
    }
    return 0;
}


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