Accepted

Author: gouthampradhan

problems/src/WordBreakII.java

@@ -0,0 +1,60 @@
+import java.util.*;
+
+/**
+ * Created by gouthamvidyapradhan on 07/04/2017.
+ * Accepted
+ */
+public class WordBreakII
+{
+    private Map<Integer, List<String>> map;
+    /**
+     * Main method
+     * @param args
+     * @throws Exception
+     */
+    public static void main(String[] args) throws Exception
+    {
+        List<String> wordList = new ArrayList<>();
+        wordList.add("cat");
+        wordList.add("cats");
+        wordList.add("and");
+        wordList.add("sand");
+        wordList.add("dog");
+        System.out.println(new WordBreakII().wordBreak("catsanddog", wordList));
+    }
+
+    public List<String> wordBreak(String s, List<String> wordDict)
+    {
+        if(s == null) return new ArrayList<>();
+        map = new HashMap<>();
+        Set<String> dictionary = new HashSet<>();
+        dictionary.addAll(wordDict);
+        return dp(0, s, s.length(), dictionary);
+    }
+
+    private List<String> dp(int p, String s, int l, Set<String> dictionary)
+    {
+        List<String> result = new ArrayList<>();
+        if(p >= s.length())
+        {
+            result.add("");
+            return result;
+        }
+        else if(map.containsKey(p))
+        {
+            return map.get(p);
+        }
+        for(int i = p; i < l; i ++)
+        {
+            String subStr = s.substring(p, i + 1);
+            if(dictionary.contains(subStr))
+            {
+                List<String> subList = dp(i + 1, s, l, dictionary);
+                for(String se : subList)
+                    result.add((subStr + " " + se).trim());
+            }
+        }
+        map.put(p, result);
+        return result;
+    }
+}