compact code for unreadability

main.mjs

@@ -30,8 +30,18 @@ const grades = [
 	}
 ]
 
+/**
+ * Returns the grade corresponding to mark.
+ *
+ * @param {number} input The marks out of 100.
+ * @return The corresponding grade of the marks.
+ * @customfunction
+ */
+
 function getGrade(mark){
-	if (typeof(mark) != 'number')
+
+	if (isNaN(Number(mark))) return 'Ab'
+
 	for (let i=0;i<=grades.length-1;i++){
 		const {max} = grades[i]
 		printdebug({i,max})
@@ -54,8 +64,4 @@ function getGrade(mark){
 const grade = getGrade(argv[2])
 console.log(grade)
 
-function printdebug(text) {
-	if (DEBUG) {
-		console.error('DEBUG:',text)
-	}
-}
+function printdebug(text){ if (DEBUG)console.error('DEBUG:',text) }