Pentaho和Hadoop(Pentaho and Hadoop)

 考虑一个有向图，每个字母都有一个顶点，每个单词都有一个边。 
 
 所以单词“cat”将对应于从顶点“c”到顶点“t”的有向边。 
 
 在此图中，您试图查看是否存在欧拉路径 。 
 
 检查Eulerian路径可以按照Wiki页面上的说明完成： 
 
 
 
 当且仅当最多一个顶点具有（out-degree） - （in-degree）= 1时，有向图具有欧拉轨迹，最多一个顶点具有（度数） - （out-degree）= 1，每个其他顶点具有相等的in-degree和out-degree，并且所有具有非零度数的顶点都属于底层无向图的单个连通分量。 
 
 
 例 
 
 
 在这张图片中，我们可以通过旅行“c” - >“t” - >“b” - >“t”来旅行所有边缘。 
 
 这是一条欧拉路径（沿着所有边缘行进），对应于单词cat，tab，bat。 

Consider a directed graph which has a vertex for each letter, and an edge for each word.
 
So the word "cat" would correspond to a directed edge from vertex "c" to vertex "t".
 
In this graph you are trying to see whether there is an Eulerian path.
 
Checking for an Eulerian path can be done as described on the wiki page:
 
 
 
A directed graph has an Eulerian trail if and only if at most one vertex has (out-degree) − (in-degree) = 1, at most one vertex has (in-degree) − (out-degree) = 1, every other vertex has equal in-degree and out-degree, and all of its vertices with nonzero degree belong to a single connected component of the underlying undirected graph.
 
 
Example
 
 
In this picture we can travel all edges by travelling "c"->"t"->"b"->"t".
 
This is an Eulerian path (it travels along all edges), and corresponds to the words cat,tab,bat.