refactor 516

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_516.java

@@ -3,7 +3,8 @@
 /**
  * 516. Longest Palindromic Subsequence
  *
- * Given a string s, find the longest palindromic subsequence's length in s. You may assume that the maximum length of s is 1000.
+ * Given a string s, find the longest palindromic subsequence's length in s.
+ * You may assume that the maximum length of s is 1000.
 
  Example 1:
  Input:
@@ -21,8 +22,13 @@
  */
 public class _516 {
 
-    /**Inspired by https://discuss.leetcode.com/topic/78603/straight-forward-java-dp-solution*/
-    public static int longestPalindromeSubseq(String s) {
+    /**
+     * Inspired by https://discuss.leetcode.com/topic/78603/straight-forward-java-dp-solution
+     * dp[i][j] means the longest palindromic subsequence's length of substring(i, j)
+     * so, in the end, we return dp[0][s.length() - 1] which means the longest palindromic subsequence
+     * of this whole string.
+     */
+    public int longestPalindromeSubseq(String s) {
         int[][] dp = new int[s.length()][s.length()];
         for (int i = s.length() - 1; i >= 0; i--) {
             dp[i][i] = 1;//initialization
@@ -37,9 +43,4 @@ public static int longestPalindromeSubseq(String s) {
         return dp[0][s.length() - 1];
     }
 
-    public static void main(String... args) {
-        longestPalindromeSubseq("bbbab");
-        System.out.println("Done.");
-    }
-
 }

src/test/java/com/fishercoder/_516Test.java

@@ -0,0 +1,22 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._516;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static junit.framework.Assert.assertEquals;
+
+public class _516Test {
+    private static _516 test;
+
+    @BeforeClass
+    public static void setup() {
+        test = new _516();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(4, test.longestPalindromeSubseq("bbbab"));
+    }
+
+}