refactor 409

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_409.java

@@ -1,5 +1,8 @@
 package com.fishercoder.solutions;
 
+import java.util.HashMap;
+import java.util.Map;
+
 public class _409 {
     public static class Solution1 {
         public int longestPalindrome(String s) {
@@ -26,4 +29,32 @@ public int longestPalindrome(String s) {
             return hasOdd ? len + 1 : len;
         }
     }
+
+    public static class Solution2 {
+        /**
+         * My completely original solution on 10/14/2021.
+         */
+        public int longestPalindrome(String s) {
+            Map<Character, Integer> map = new HashMap<>();
+            for (char c : s.toCharArray()) {
+                map.put(c, map.getOrDefault(c, 0) + 1);
+            }
+            int ans = 0;
+            boolean hasOdd = false;
+            for (char key : map.keySet()) {
+                if (map.getOrDefault(key, 0) % 2 == 0) {
+                    ans += map.getOrDefault(key, 0);
+                } else {
+                    hasOdd = true;
+                    if (map.containsKey(key)) {
+                        ans += map.getOrDefault(key, 0) - 1;
+                    }
+                }
+            }
+            if (hasOdd) {
+                ans++;
+            }
+            return ans;
+        }
+    }
 }

src/test/java/com/fishercoder/_409Test.java

@@ -7,31 +7,38 @@
 import static org.junit.Assert.assertEquals;
 
 public class _409Test {
-  private static _409.Solution1 solution1;
-
-  @BeforeClass
-  public static void setup() {
-    solution1 = new _409.Solution1();
-  }
-
-  @Test
-  public void test1() {
-    assertEquals(7, solution1.longestPalindrome("abccccdd"));
-  }
-
-  @Test
-  public void test2() {
-    assertEquals(7, solution1.longestPalindrome("abccAccdd"));
-  }
-
-  @Test
-  public void test3() {
-    assertEquals(983, solution1.longestPalindrome(
-        "civilwartestingwhetherthatnaptionoranynartionsoconceivedandsodedicatedcanlongendureWeareqmetonagreatbattlefiemldoftzhatwarWehavecometodedicpateaportionofthatfieldasafinalrestingplaceforthosewhoheregavetheirlivesthatthatnationmightliveItisaltogetherfangandproperthatweshoulddothisButinalargersensewecannotdedicatewecannotconsecratewecannothallowthisgroundThebravelmenlivinganddeadwhostruggledherehaveconsecrateditfaraboveourpoorponwertoaddordetractTgheworldadswfilllittlenotlenorlongrememberwhatwesayherebutitcanneverforgetwhattheydidhereItisforusthelivingrathertobededicatedheretotheulnfinishedworkwhichtheywhofoughtherehavethusfarsonoblyadvancedItisratherforustobeherededicatedtothegreattdafskremainingbeforeusthatfromthesehonoreddeadwetakeincreaseddevotiontothatcauseforwhichtheygavethelastpfullmeasureofdevotionthatweherehighlyresolvethatthesedeadshallnothavediedinvainthatthisnationunsderGodshallhaveanewbirthoffreedomandthatgovernmentofthepeoplebythepeopleforthepeopleshallnotperishfromtheearth"));
-  }
-
-  @Test
-  public void test4() {
-    assertEquals(3, solution1.longestPalindrome("ccc"));
-  }
+    private static _409.Solution1 solution1;
+    private static _409.Solution2 solution2;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _409.Solution1();
+        solution2 = new _409.Solution2();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(7, solution1.longestPalindrome("abccccdd"));
+        assertEquals(7, solution2.longestPalindrome("abccccdd"));
+    }
+
+    @Test
+    public void test2() {
+        assertEquals(7, solution1.longestPalindrome("abccAccdd"));
+        assertEquals(7, solution2.longestPalindrome("abccAccdd"));
+    }
+
+    @Test
+    public void test3() {
+        assertEquals(983, solution1.longestPalindrome(
+                "civilwartestingwhetherthatnaptionoranynartionsoconceivedandsodedicatedcanlongendureWeareqmetonagreatbattlefiemldoftzhatwarWehavecometodedicpateaportionofthatfieldasafinalrestingplaceforthosewhoheregavetheirlivesthatthatnationmightliveItisaltogetherfangandproperthatweshoulddothisButinalargersensewecannotdedicatewecannotconsecratewecannothallowthisgroundThebravelmenlivinganddeadwhostruggledherehaveconsecrateditfaraboveourpoorponwertoaddordetractTgheworldadswfilllittlenotlenorlongrememberwhatwesayherebutitcanneverforgetwhattheydidhereItisforusthelivingrathertobededicatedheretotheulnfinishedworkwhichtheywhofoughtherehavethusfarsonoblyadvancedItisratherforustobeherededicatedtothegreattdafskremainingbeforeusthatfromthesehonoreddeadwetakeincreaseddevotiontothatcauseforwhichtheygavethelastpfullmeasureofdevotionthatweherehighlyresolvethatthesedeadshallnothavediedinvainthatthisnationunsderGodshallhaveanewbirthoffreedomandthatgovernmentofthepeoplebythepeopleforthepeopleshallnotperishfromtheearth"));
+        assertEquals(983, solution2.longestPalindrome(
+                "civilwartestingwhetherthatnaptionoranynartionsoconceivedandsodedicatedcanlongendureWeareqmetonagreatbattlefiemldoftzhatwarWehavecometodedicpateaportionofthatfieldasafinalrestingplaceforthosewhoheregavetheirlivesthatthatnationmightliveItisaltogetherfangandproperthatweshoulddothisButinalargersensewecannotdedicatewecannotconsecratewecannothallowthisgroundThebravelmenlivinganddeadwhostruggledherehaveconsecrateditfaraboveourpoorponwertoaddordetractTgheworldadswfilllittlenotlenorlongrememberwhatwesayherebutitcanneverforgetwhattheydidhereItisforusthelivingrathertobededicatedheretotheulnfinishedworkwhichtheywhofoughtherehavethusfarsonoblyadvancedItisratherforustobeherededicatedtothegreattdafskremainingbeforeusthatfromthesehonoreddeadwetakeincreaseddevotiontothatcauseforwhichtheygavethelastpfullmeasureofdevotionthatweherehighlyresolvethatthesedeadshallnothavediedinvainthatthisnationunsderGodshallhaveanewbirthoffreedomandthatgovernmentofthepeoplebythepeopleforthepeopleshallnotperishfromtheearth"));
+    }
+
+    @Test
+    public void test4() {
+        assertEquals(3, solution1.longestPalindrome("ccc"));
+        assertEquals(3, solution2.longestPalindrome("ccc"));
+    }
 }