spfa组长版本！

#include<cstdio>
#include<iostream>
#include<queue>
#include<cstring>
using namespace std;
const int maxn = 10010;
typedef long long ll;
const ll INF = 1e18;
struct Side{
    int to,next;
    ll w;
}side[50010];
int top;
int node[maxn];
void add_side(int u,int v,ll w){
    side[top]=(Side){v,node[u],w};
    node[u]=top++;
}
ll dis[maxn];
bool inqueue[maxn];
int n,m;
queue<int>q;
ll spfa(int S,int T){
    for(int i=1;i<=n;i++){
        inqueue[i]=false;
        dis[i]=INF;
    }
    q.push(S);
    dis[S]=0;
    while(!q.empty()){
        int u = q.front();q.pop();
        inqueue[u]=false;
        for(int i=node[u];i!=-1;i=side[i].next){
            int v=side[i].to;
            if(dis[u]+side[i].w<dis[v]){
                dis[v]=dis[u]+side[i].w;
                if(!inqueue[v]){
                    inqueue[v]=true;
                    q.push(v);
                }
            }
        }
    }
    return dis[T];
}
int main(){
    int t;
    scanf("%d",&t);
    while(t--){
        scanf("%d%d",&n,&m);
        top=0;
        memset(node,-1,sizeof(node));
        for(int i=0;i<m;i++){
            int u,v;
            ll w;
            scanf("%d%d%lld",&u,&v,&w);
            add_side(u,v,w);
        }
        int a,b,c;
        scanf("%d%d%d",&a,&b,&c);
        ll ans=0;
        ans+=spfa(a,b);
        ans+=spfa(b,c);
        cout<<ans<<endl;
    }
}

spfa组长版本！,布布扣,bubuko.com

spfa组长版本！

原文：http://blog.csdn.net/u013889359/article/details/22947403