Create checkDigit.js

checkDigit.js

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+// Finding the checkDigit of a barcode
+let number = 36000291452;
+let strNum = number.toString();
+let arr = strNum.split('');
+let even = [];
+let odd = [];
+for(let i = 0; i < arr.length; i++) {
+    let counter = i + 1;
+    if((counter % 2) == 0) {
+ even.push(arr[i]);
+    } else {
+        odd.push(arr[i]);
+    }
+
+}
+
+let multiplyOdd = odd.map((x  => x *3));
+let sumOdd = multiplyOdd.reduce((acc,val) => acc+val);
+let evenNumber = even.map((x => Number(x)) );
+let sumEven = evenNumber.reduce((acc,val) => acc + val);
+let total = sumOdd+ sumEven;
+
+let remainder = total % 10;
+let checkDigit = 10 -remainder;
+console.log(` The checkDigit is ${checkDigit}`);