my sum solution

Author: Ogbemi mene

Sprint-1/implement/sum.js

@@ -1,4 +1,16 @@
 function sum(elements) {
+    if (!Array.isArray(elements) || elements.length === 0) {
+    return 0;
+  }
+
+  const numbersOnly = elements.filter(item => typeof item === "number" && !isNaN(item));
+
+  if (numbersOnly.length === 0) {
+    return 0;
+  }
+
+  return numbersOnly.reduce((acc, curr) => acc + curr, 0);
+
 }
 
 module.exports = sum;