poj1125 Stockbroker Grapevine 最短路 dijkstral + 优先队列

//    poj1125 Stockbroker Grapevine 最短路 dijkstral + 优先队列
//
//    一个模板吧，留着纪念

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <queue>

using namespace std;

typedef pair<int,int> P;

const int MAX_N = 108;
const int INF = 0x3f3f3f3f;
struct node {
    int to;
    int w;
    int next;

    node (){

    }

    node (int to,int w,int next):to(to),w(w),next(next){

    }
};

node edges[MAX_N * MAX_N];

int head[MAX_N];

int num;
int n,m;
bool vis[MAX_N];

void add_edge(int u,int v,int w){
    edges[num].to = v;
    edges[num].w = w;
    edges[num].next = head[u];
    head[u] = num++;
}

void input(){
    memset(head,-1,sizeof(head));
    num = 0;
    int v,w;
    for (int i=1;i<=n;i++){
        scanf("%d",&m);
        for (int j=1;j<=m;j++){
            scanf("%d%d",&v,&w);
            add_edge(i,v,w);
        }
    }
}

int dijkstra(int s){
    int d[MAX_N];
    memset(d,INF,sizeof(d));
    memset(vis,0,sizeof(vis));
    d[s] = 0;
    vis[s] = 1;
    priority_queue<P,vector<P>,greater<P> > que;
    que.push(P(0,s));

    while(!que.empty()){
        P x = que.top();
        que.pop();
        int u = x.second;
        if (x.first > d[u])    continue;
        for (int j = head[u] ; j!=-1;j=edges[j].next){
            int v = edges[j].to;
            int w = edges[j].w;
            if (d[v] > d[u] + w){
                d[v] = d[u] + w;
                que.push(P(d[v],v));
            }
        }
    }
    int mx = 0;
    for (int i=1;i<=n;i++){
        if (d[i]==INF){
            return -1;
        }
        else if (d[i] > mx){
            mx = d[i];
        }
    }
    return mx;

}

void solve(){
    int k = -1;
    int mx = INF;
    for (int i=1;i<=n;i++){
        int x = dijkstra(i);
        if (x!=-1){
            if (mx > x){
                k = i;
                mx = x;
            }
        }
    }
    printf("%d %d\n",k,mx);
}

int main(){
    //freopen("1.txt","r",stdin);
    while(scanf("%d",&n)!=EOF && n){
        input();
        solve();
    }
}

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