Unformatted text preview: 2 You are given a tree T , having n vertices (rooted at vertex r for convenience). You are also given k pairs ( x i , y i ) , 1 ≤ i ≤ k . The task is to output for each pair ( x i , y i ) whether x i is an ancestor of y i in tree T (that is, output yes if x i is an ancestor of y i , and no if it is not). Note that x i is an ancestor of y i can be reframed as y i is in the subtree rooted at x i for convenience. Your algorithm should take O ( n + k ) time. Hint : Think about the graph traversal methods you learned in class. 1...
View
Full Document
 Fall '11
 Staff
 Graph Theory, Yi, Graph traversal methods, CatalinStefan Tiseanu, challenge homework problems

Click to edit the document details