#409 最长回文串 贪心算法

Author: Isaaclot

main/src/greedy/LC_409_LongestPalindrome.java

@@ -0,0 +1,21 @@
+package greedy;
+
+/**
+ * @author liangqian0723@gmail.com
+ * @since 2020/3/19 11:32 PM
+ */
+public class LC_409_LongestPalindrome {
+    public int longestPalindrome(String s) {
+        if (null == s) return 0;
+        int[] chars = new int[128];
+        for (char c : s.toCharArray()) {
+            chars[c]++;
+        }
+        int res = 0;
+        for (int c : chars) {
+            res += c / 2 * 2;
+            if (res % 2 == 0 && c % 2 == 1) res++;
+        }
+        return res;
+    }
+}

main/test/greedy/LC_409_LongestPalindromeTest.java

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+package greedy;
+
+import org.junit.Test;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author liangqian0723@gmail.com
+ * @since 2020/3/19 11:31 PM
+ */
+public class LC_409_LongestPalindromeTest {
+    @Test
+    public void test_longest_palindrome() {
+        LC_409_LongestPalindrome lp = new LC_409_LongestPalindrome();
+        assertThat(lp.longestPalindrome("abccccdd"), is(7));
+    }
+}