delete pics to save space

2.1599.cpp

@@ -0,0 +1,101 @@
+#include<cstdio>
+#include<cstring>
+#include<queue>
+using namespace std;
+const int MAXN=100000;
+struct node
+{
+	int v,c;
+	node *next;
+}edge[MAXN*4+10];
+node *adj[MAXN+10];
+node *ecnt=edge;
+inline void addedge(int u,int v,int c)
+{
+	node *p=++ecnt;
+	p->v=v;
+	p->c=c;
+	p->next=adj[u];
+	adj[u]=p;
+}
+int d[MAXN+10],path[MAXN+10];
+bool vis[MAXN+10];
+queue<int> q;
+int n,m;
+void bfs1(int s)
+{
+	memset(d,0,sizeof(d));
+	d[s]=1;
+	q.push(s);
+	while (!q.empty())
+	{
+		int u=q.front();
+		q.pop();
+		for(node *p=adj[u];p;p=p->next)
+		{
+			int v=p->v;
+			if(!d[v])
+			{
+				d[v]=d[u]+1;
+				q.push(v);
+			}
+		}
+	}
+}
+queue<pair<int,int>> q2;
+void bfs2(int s)
+{
+	memset(path,0x3f,sizeof(path));
+	memset(vis,0,sizeof(vis));
+	q2.push(make_pair(s,0));
+	path[0]=0;
+	while(!q2.empty())
+	{
+		int u=q2.front().first;
+		int cy=q2.front().second;
+		q2.pop();
+		if(path[d[1]-d[u]]!=cy||vis[u]) continue;
+		vis[u]=true;
+		for (node *p=adj[u];p;p=p->next)
+		{
+			int v=p->v;
+			int c=p->c;
+			if (d[u] != d[v] + 1 || path[d[1] - d[v]] <= c) continue;
+			path[d[1]-d[v]]=c;
+		}
+		for(node *p=adj[u];p;p=p->next)
+		{
+			int v=p->v;
+			int c=p->c;
+			if(d[u]!=d[v]+1||path[d[1]-d[v]]!=c) continue;
+			q2.push(make_pair(v,c));
+		}
+	}
+	d[1]--;
+	int i;
+	printf("%d\n",d[1]);
+	for(i=1;i<=d[1];i++)
+		printf("%d%c",path[i],i==d[1]?'\n':' ');
+}
+
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	int u,v,w,i;
+	while(scanf("%d%d",&n,&m)==2)
+	{
+		memset(adj,0,sizeof(adj));
+		ecnt=edge;
+		for(i=1;i<=m;i++)
+		{
+			scanf("%d%d%d",&u,&v,&w);
+			addedge(u,v,w);
+			addedge(v,u,w);
+		}
+		bfs1(n);
+		bfs2(1);
+	}
+	return 0;
+}