Create 409.最长回文串.js

Author: yinxin630

409.最长回文串.js

@@ -0,0 +1,17 @@
+/**
+ * @param {string} s
+ * @return {number}
+ */
+var longestPalindrome = function(s) {
+    const arr = new Array(128).fill(0);
+    let result = 0;
+    for (let i = 0; i < s.length; i++) {
+        const n = s.charCodeAt(i);
+        arr[n]++;
+        if (arr[n] >= 2) {
+            result += 2;
+            arr[n] -= 2;
+        }
+    }
+    return result + (arr.indexOf(1) === -1 ? 0 : 1);
+};