hdu 3191 How Many Paths Are There

#include <cstdio>
#include <cstring>
#include <vector>
#include <queue>
#include <algorithm>
#define maxn 2000
using namespace std;
const int inf=1<<30;
struct edge
{
int v,w;
};

struct node
{
int d,v;
int mark;
bool operator < (const node &a)const
{
if(d!=a.d)
return d>a.d;
return v>a.v;
}
};

vector<edge>edges[maxn];
int dis[maxn][3];
int vis[maxn][3];
int path[maxn][3];
int n,m,a,b,c,s1,f;
node st;

void inti()
{
for(int i=0; i<=n; i++)
{
dis[i][1]=dis[i][2]=inf;
}
memset(path,0,sizeof(path));
memset(vis,false,sizeof(vis));
}

void dijkstra(int s,int e)
{
inti();
priority_queue<node>q;
dis[s][1]=0;
path[s][1]=1;
memset(vis,false,sizeof(vis));
st.d=0;
st.v=s;
st.mark=1;
q.push(st);
while(!q.empty())
{
node st1=q.top();
q.pop();
if(vis[st1.v][st1.mark]) continue;
vis[st1.v][st1.mark]=true;
for(int i=0; i<(int)edges[st1.v].size(); i++)
{
int v1=edges[st1.v][i].v;
int w1=edges[st1.v][i].w;
if(!vis[v1][1]&&st1.d+w1<dis[v1][1])
{
if(dis[v1][1]!=inf)
{
dis[v1][2]=dis[v1][1];
path[v1][2]=path[v1][1];
st.d=dis[v1][2];
st.v=v1;
st.mark=2;
q.push(st);
}
dis[v1][1]=st1.d+w1;
path[v1][1]=path[st1.v][st1.mark];
st.v=v1;
st.mark=1;
st.d=dis[v1][1];
q.push(st);
}
else if(!vis[v1][1]&&st1.d+w1==dis[v1][1])
{
path[v1][1]+=path[st1.v][st1.mark];
}
else if(!vis[v1][2]&&st1.d+w1<dis[v1][2])
{
dis[v1][2]=st1.d+w1;
path[v1][2]=path[st1.v][st1.mark];
st.d=dis[v1][2];
st.v=v1;
st.mark=2;
q.push(st);
}
else if(!vis[v1][2]&&st1.d+w1==dis[v1][2])
{
path[v1][2]+=path[st1.v][st1.mark];
}
}
}
}

int main()
{
while(scanf("%d%d%d%d",&n,&m,&s1,&f)!=EOF)
{
inti();
for(int i=0; i<=n; i++) edges[i].clear();
for(int i=0; i<m; i++)
{
scanf("%d%d%d",&a,&b,&c);
edge m1;
m1.v=b;
m1.w=c;
edges[a].push_back(m1);
}
dijkstra(s1,f);
printf("%d %d\n",dis[f][2],path[f][2]);
}
return 0;
}