Update 866-prime-palindrome.js

Author: everthis

866-prime-palindrome.js

@@ -1,3 +1,28 @@
+/**
+ * @param {number} n
+ * @return {number}
+ */
+const primePalindrome = function(n) {
+  if(n >= 8 && n <= 11) return 11
+  const rev = str => str.split('').reverse().join('')
+  for (let i = 1; i < 1e5; i++) {
+    let left = `${i}`, right = rev(left).slice(1)
+    let num = +(left + right)
+    if (num >= n && isPrime(num)) return num
+  }
+  return -1
+
+  function isPrime(num) {
+    if(num < 2 || num % 2 === 0) return num === 2
+    for(let i = 3; i * i <= num; i += 2) {
+      if(num % i === 0) return false
+    }
+    return true
+  }
+};
+
+// another
+
 /**
  * @param {number} N
  * @return {number}