Cracking the Coding Interview, 4 Edition - 150 Programming Interview Questions and Solutions

Solutions to Chapter 20 | Hard
20.8 Given a string s and an array of smaller strings T, design a method to search s for each
small string in T.
SOLUTION
pg 91
First, create a suffix tree for s. For example, if your word were bibs, you would create the following
tree:
B
I
S
I
S
B
B
S
S
Then, all you need to do is search for each string in T in the suffix tree. Note that if “B” were a
word, you would come up with two locations.
1 public class SuffixTree {
2 SuffixTreeNode root = new SuffixTreeNode();
3 public SuffixTree(String s) {
4 for (int i = 0; i < s.length(); i++) {
5 String suffix = s.substring(i);
6 root.insertString(suffix, i);
7 }
8 }
9
10 public ArrayList getIndexes(String s) {
11 return root.getIndexes(s);
12 }
13 }
14
15 public class SuffixTreeNode {
16 HashMap children = new
17 HashMap();
18 char value;
19 ArrayList indexes = new ArrayList();
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