delete pics to save space

1.1948.cpp

@@ -0,0 +1,56 @@
+#include<cstdio>
+#include<cstring>
+#include<deque>
+#include<algorithm>
+using namespace std;
+const int maxn=1005;
+const int maxm=20005;
+struct Edge { int v,w; Edge *nxt; };
+Edge mem[maxm],*G[maxn],*ecnt=mem;
+inline void AddEdge(int u,int v,int w) { ecnt->v=v; ecnt->w=w; ecnt->nxt=G[u]; G[u]=ecnt++; }
+int n,m,k,L,R,M,res;
+int vis[maxn],d[maxn];
+inline bool check(int M)
+{
+	memset(vis,0,sizeof(vis));
+	memset(d,0x3f,sizeof(d));
+	deque<int> Q;
+	Q.push_back(1); d[1]=0;
+	while(Q.size())
+	{
+		int u=Q.front(); Q.pop_front();
+		vis[u]=1;
+		for(Edge *it=G[u];it;it=it->nxt)
+		{
+			int w=(it->w>M);
+			if(vis[it->v]||d[u]+w>=d[it->v]) continue;
+			d[it->v]=d[u]+w;
+			if(!w) Q.push_front(it->v);
+			else Q.push_back(it->v);
+		}
+	}
+	return d[n]<=k;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d%d",&n,&m,&k);
+	for(int i=1;i<=m;i++)
+	{
+		int u,v,w; scanf("%d%d%d",&u,&v,&w);
+		AddEdge(u,v,w); AddEdge(v,u,w);
+		R=max(R,w);
+	}
+	R++; int oo=res=R;
+	while(L<=R)
+	{
+		M=(L+R)>>1;
+		if(check(M)) res=M,R=M-1;
+		else L=M+1;
+	}
+	if(res==oo) puts("-1");
+	else printf("%d\n",res);
+	return 0;
+}