[N-0] refactor 139

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_139.java

@@ -5,6 +5,7 @@
 
 /**
  * 139. Word Break
+ *
  * Given a non-empty string s and a dictionary wordDict containing a list of non-empty words,
  * determine if s can be segmented into a space-separated sequence of one or more dictionary words.
  * You may assume the dictionary does not contain duplicate words.
@@ -22,10 +23,8 @@ The wordDict parameter had been changed to a list of strings (instead of a set o
 
 public class _139 {
 
-    public static class PureDPSolution {
-        /**
-         * This beats 70.10% submissions.
-         */
+    public static class Solution1 {
+        /**this beats 70.46% submission. */
         public boolean wordBreak(String s, List<String> wordDict) {
             int n = s.length();
             boolean[] dp = new boolean[n + 1];
@@ -42,9 +41,10 @@ public boolean wordBreak(String s, List<String> wordDict) {
         }
     }
 
-    public static class ModifiedDPAndPruningSolution {
+    public static class Solution2 {
         /**
-         * This beats 86.09% submissions.
+         * Added pruning.
+         * this beats 89.91% submissions.
          */
         public boolean wordBreak(String s, List<String> wordDict) {
             int maxLen = Integer.MIN_VALUE;
@@ -70,9 +70,10 @@ public boolean wordBreak(String s, List<String> wordDict) {
         }
     }
 
-    public static class DPAndPruningSolution {
+    public static class Solution3 {
         /**
-         * This beats 97.08% submissions.
+         * Added pruning, plus start from the end to check.
+         * This beats 95.20% submissions.
          */
         public boolean wordBreak(String s, Set<String> wordDict) {
             int maxLen = Integer.MIN_VALUE;

src/test/java/com/fishercoder/_139Test.java

@@ -11,19 +11,19 @@
 import static junit.framework.Assert.assertEquals;
 
 public class _139Test {
-    private static _139.ModifiedDPAndPruningSolution modifiedDpAndPruningSolution;
+    private static _139.Solution2 solution2;
     private static String s;
     private static List<String> wordDict;
 
     @BeforeClass
     public static void setup() {
-        modifiedDpAndPruningSolution = new _139.ModifiedDPAndPruningSolution();
+        solution2 = new _139.Solution2();
     }
 
     @Test
     public void test1() {
         s = "leetcode";
         wordDict = new ArrayList<>(Arrays.asList("leet", "code"));
-        assertEquals(true, modifiedDpAndPruningSolution.wordBreak(s, wordDict));
+        assertEquals(true, solution2.wordBreak(s, wordDict));
     }
 }