delete pics to save space

history_source/信息学奥赛一本通/3.4.3.2.cpp

@@ -0,0 +1,35 @@
+#include<cstdio>
+int n,m,i,j,k,a[5000]={0},g[5000][5000],s;
+char as;
+inline int min(int a,int b)
+{return a<b?a:b;}
+int main()
+{
+	freopen("travel.in","r",stdin);
+	freopen("travel.out","w",stdout);
+	scanf("%d%d",&m,&n);
+	for(i=1;i<=m;i++)
+	{
+		s=0;
+		as=1;
+		while(as!='\n')
+		{
+			s++;
+			scanf("%d",a+s);
+			as=getchar();
+		}
+		for(j=1;j<=s-1;j++)
+			for(k=j+1;k<=s;k++)
+				g[a[j]][a[k]]=1;
+	}
+	for(i=1;i<=n;i++)
+		for(j=1;j<=n;j++)
+			if(g[i][j]==0)  g[i][j]=100000;
+	for(k=1;k<=n;k++)
+		for(i=1;i<=n;i++)
+			for(j=1;j<=n;j++)
+				g[i][j]=min(g[i][j],g[i][k]+g[k][j]);
+	if (g[1][n]>=100000) printf("NO\n");
+	else printf("%d",g[1][n]-1);
+	return 0;
+}