最短路之SPFA模板

bool SPFA()
{
int V;
int edge;
bool vis[maxn];
int dist[maxn];
int queuenum[maxn];
int maps[maxn][maxn];
memset(vis,false,sizeof(vis));
memset(queuenum,0,sizeof(queuenum));
memset(dist,INF,sizeof(INF));
dist[0] = 0;
queue < int > q;
q.push(source);
vis[source] = true;
queuenum[source] = 1;
while(!q.empty())
{
int u = q.front();
q.pop();
vis[u] = false;
for(int i=0; i<V; i++)
{
if(maps[u][i] != INF)
{
if(dist[u] + maps[u][i] < dist[i])
{
dist[i] = dist[u] + maps[u][i];
if(!vis[i])
{
q.push(i);
queuenum[i]++;
if(queuenum[i] >= V)
return false;
vis[i] = true;
}
}
}
}
}
return true;
}