AOJ 2249 Road Construction 最短路径 Dijkstra算法优化

#include 
#include 
#include 
using namespace std;
struct Edge
{
    int to, len, cost;
    Edge(int to = 0, int len = 0, int cost = 0) : to(to), len(len), cost(cost) {}
};
typedef pair P;
vector edges[10007];
int inf = 0x3f3f3f3f, N, M, d[10007], ans[10007];
bool used[10007];
void input()
{
    int from, to, len, cost;
    for (int i = 1; i <= M; i++)
    {
        scanf("%d%d%d%d", &from, &to, &len, &cost);
        edges[from].push_back(Edge(to, len, cost));
        edges[to].push_back(Edge(from, len, cost));
    }
}
void dijkstra()
{
    for (int i = 1; i <= N; i++)
    {
        d[i] = inf;
        used[i] = false;
        ans[i] = inf;
    }
    d[1] = 0;
    ans[1] = 0;
    priority_queue, greater
> que;
    que.push(P(0, 1));
    while (!que.empty())
    {
        P current = que.top();
        que.pop();
        if (used[current.second] || current.first > d[current.second])
        {
            continue;
        }
        used[current.second] = true;
        for (int i = 0; i < edges[current.second].size(); i++)
        {
            Edge toEdge = edges[current.second][i];
            if (d[current.second] + toEdge.len < d[toEdge.to])
            {
                d[toEdge.to] = d[current.second] + toEdge.len;
                ans[toEdge.to] = toEdge.cost;
                que.push(P(d[toEdge.to], toEdge.to));
            }
            if (d[current.second] + toEdge.len == d[toEdge.to] && toEdge.cost < ans[toEdge.to])
            {
                ans[toEdge.to] = toEdge.cost;
            }
        }
    }
}
void solve()
{
    dijkstra();
    int res = 0;
    for (int i = 1; i <= N; i++)
    {
        res += ans[i];
    }
    printf("%d\n", res);
}
void clearAll()
{
    for (int i = 1; i <= N; i++)
    {
        edges[i].clear();
    }
}
int main()
{
    while (true)
    {
        scanf("%d%d", &N, &M);
        if (N == 0 && M == 0)
        {
            break;
        }
        input();
        solve();
        clearAll();
    }
    return 0;
}