hdu 3191 次短路

#include<iostream>
#include<cstdio>
#include<queue>
#include<string>
#include<vector>
#define INF 0x7fffffff
using namespace std;
const int V = 52;
const int E = 6005;
int n,m,s,t;
int dist[V][3],cnt[V][3];
bool hash[V][3];
struct Edge{
int v,c;
Edge(int vv = 0, int cc = 0):v(vv),c(cc){}
};
vector<Edge>edge[V];
struct node{
int vexn,dist,flag;
node(int vv = 0, int dd = 0, int ff = 0):vexn(vv),dist(dd),flag(ff){}
bool operator<(const node &a)const
{
return dist != a.dist?dist > a.dist:vexn > a.vexn;
}
};
bool djkstra(int src,int n,int e)
{
priority_queue<node> q;
int i,v,k,c;
node N;
for(i = 0; i< n; i++)
{
dist[i][0] = dist[i][1] = INF;
}
memset(hash,false,sizeof(hash));
cnt[src][0] = 1;
dist[src][0] = 0;
q.push(node(src,0,0));
while(!q.empty())
{
N = q.top();
q.pop();
if(dist[N.vexn][N.flag] != N.dist)continue;
if(hash[N.vexn][N.flag])continue;
hash[N.vexn][N.flag] = true;
for(i = 0; i < edge[N.vexn].size(); i++)
{
v = edge[N.vexn][i].v;
c = edge[N.vexn][i].c;
if(!hash[v][0] && dist[v][0] > N.dist + c)
{
if(dist[v][0] != INF)
{
dist[v][1] = dist[v][0];
cnt[v][1] = cnt[v][0];
q.push(node(v,dist[v][1],1));
}
dist[v][0] = N.dist + c;
cnt[v][0] = cnt[N.vexn][N.flag];
q.push(node(v,dist[v][0],0));
}
else if(!hash[v][0] && dist[v][0] == N.dist + c)
{
cnt[v][0] += cnt[N.vexn][N.flag];
}
else if(!hash[v][1] && dist[v][1] > N.dist + c)
{
dist[v][1] = N.dist + c;
cnt[v][1] = cnt[N.vexn][N.flag];
q.push(node(v,dist[v][1],1));
}
else if(!hash[v][1] && dist[v][1] == N.dist + c)
{
cnt[v][1] += cnt[N.vexn][N.flag];
}
// }
}
}
if(dist[e][0] == INF)
return false;
return true;
}
void solve()
{
int ss;
Edge tem;
for(int i = 0; i<= n; i++)
{
cnt[i][0] = cnt[i][1] = 0;
edge[i].clear();
}
for(int i = 1; i<= m; i++)
{
scanf("%d %d %d",&ss, &tem.v, &tem.c);
edge[ss].push_back(tem);
}
djkstra(s,n,t);
printf("%d %d/n",dist[t][1],cnt[t][1]);
}
int main()
{
while(scanf("%d

%d %d %d",&n, &m, &s, &t) != EOF)
{
solve();
}
}

//朴素dij

#include<iostream>
#include<cstdio>
#include<queue>
#include<string>
#include<vector>
#define INF 0x7fffffff
using namespace std;
const int V = 52;
const int E = 6005;
int n,m,s,t;
int dist[V][3],cnt[V][3];
bool hash[V][3];
struct Edge{
int v,c;
Edge(int vv = 0, int cc = 0):v(vv),c(cc){}
};
vector<Edge>edge[V];
bool djkstra(int src,int n,int e)
{
int i,v,k,c;
for(i = 0; i< n; i++)
{
dist[i][0] = dist[i][1] = INF;
}
memset(hash,false,sizeof(hash));
cnt[src][0] = 1;
dist[src][0] = 0;
int Min,u,flag;
for(i = 0; i <2 * n; i++)
{
Min = INF;
u = -1;
for(int j = 0; j < n; j++)
{
if(!hash[j][0] && dist[j][0] < Min)
{
u = j;
Min = dist[j][0];
flag = 0;
}
if(!hash[j][1] && dist[j][1] < Min)
{
u = j;
Min = dist[j][1];
flag = 1;
}
}
if(u == -1)
return false;
hash[u][flag] = true;
for(i = 0; i < edge[u].size(); i++)
{
v = edge[u][i].v;
c = edge[u][i].c;
if(!hash[v][0] && dist[v][0] > Min + c)
{
dist[v][1] = dist[v][0];
cnt[v][1] = cnt[v][0];
dist[v][0] = Min + c;
cnt[v][0] = cnt[u][flag];
}
else if(!hash[v][0] && dist[v][0] == Min + c)
{
cnt[v][0] += cnt[u][flag];
}
else if(!hash[v][1] && dist[v][1] > Min + c)
{
dist[v][1] = Min + c;
cnt[v][1] = cnt[u][flag];
}
else if(!hash[v][1] && dist[v][1] == Min + c)
{
cnt[v][1] += cnt[u][flag];
}
}
}
if(dist[e][0] == INF)
return false;
return true;
}
void solve()
{
int ss;
Edge tem;
for(int i = 0; i<= n; i++)
{
cnt[i][0] = cnt[i][1] = 0;
edge[i].clear();
}
for(int i = 1; i<= m; i++)
{
scanf("%d %d %d",&ss, &tem.v, &tem.c);
edge[ss].push_back(tem);
}
djkstra(s,n,t);
printf("%d %d/n",dist[t][1],cnt[t][1]);
}
int main()
{
while(scanf("%d %d %d %d",&n, &m, &s, &t) != EOF)
{
solve();
}
}