spfa跑最长路板子

void spfa(int s)//spfa跑最长路
{
    memset(dis, -1, sizeof(dis));
    memset(V, 0, sizeof(V));
    dis[s] = sum[s];
    V[s] = 1;
    q.push(s);
    while (!q.empty())
    {
        int u = q.front();
        q.pop();
        V[u] = 0;
        for (int i = H[u]; i; i = E[i].next)
        {
            int v = E[i].to, w = E[i].val;
            if (dis[v] < dis[u] + w + sum[v])
            {
                dis[v] = dis[u] + w + sum[v];
                if (!V[v])
                {
                    V[v] = 1;
                    q.push(v);
                }
            }
        }
    }
}