140. Word Break II (java)

Author: bluesword12350

solution/0140.Word Break II/Solution.java

@@ -0,0 +1,23 @@
+class Solution {
+    public List<String> wordBreak(String s, List<String> wordDict) {
+        return wordBreak(s,wordDict,new HashMap<>(16));
+    }
+    private List<String> wordBreak(String s, List<String> wordDict, HashMap<String, List<String>> map) {
+        List<String> list=new ArrayList<>();
+        if(map.containsKey(s))  return map.get(s);
+        if("".equals(s)){
+            list.add("");
+            return list;
+        }
+        for(String word:wordDict){
+            if(s.startsWith(word)){
+                List<String> res=wordBreak(s.substring(word.length()),wordDict,map);
+                for(String str:res){
+                    list.add(word+("".equals(str) ?"":" ")+str);
+                }
+            }
+        }
+        map.put(s,list);
+        return list;
+    }
+}