UnionFind doesn't merge the connected components about neo4j-graph-algorithms

[AliciaFrame]

You're getting a different result because of your CREATE statements for the relationships - it looks like, instead of running the query as a block of code, you're running each line individually. When you use CREATE (nAlice:User {name: 'Alice'}) you temporarily create a variable (nAlice) that refers to the node with the name of Alice, however, the variable doesn't persist between queries -- so it's not available when you run CREATE (nAlice)-[:LINK {weight: 0.5}]->(nBridget).

So if you run:

CREATE (nAlice:User {name: 'Alice'})
CREATE (nBridget:User {name: 'Bridget'})
CREATE (nCharles:User {name: 'Charles'})
CREATE (nDoug:User {name: 'Doug'})
CREATE (nMark:User {name: 'Mark'})
CREATE (nMichael:User {name: 'Michael'})

CREATE (nAlice)-[:LINK {weight: 0.5}]->(nBridget)
CREATE (nAlice)-[:LINK {weight: 4}]->(nCharles)
CREATE (nMark)-[:LINK {weight: 1.1}]->(nDoug)
CREATE (nMark)-[:LINK {weight: 2}]->(nMichael);

As a single Cypher statement, then call the algo, you should get the results you expect :)