s3 Basic Data Structure ☆ Union(ij) Idea: Make S a subtree of s, or vice versa. that is, we can set the parent pointer of one of the roots to the other root. S1∪S Im plementation 1 S,∪S name[l S2 S3 ①⑨ → 2§3 Basic Data Structure ❖ Union ( i, j ) Idea: Make Si a subtree of Sj , or vice versa. That is, we can set the parent pointer of one of the roots to the other root. 10 6 8 7 4 1 9 4 1 9 10 S 6 7 8 1  S2 S2  S1 Implementation 1: S1 S2 S3 • • • name[ ] 10 6 7 8 4 1 9 2 3 5 S2  S1  S2