javascript on your machine

index.js

@@ -4,7 +4,36 @@
  * Depending on the operation, either add up all of the numbers or subtract all of the numbers, from left to right.
  * @returns {number} The result of either adding all numbers or subtracting all numbers, depending on the arguments added to the command line.
  */
-function calculator() {}
+function calculator() {
+ console.log(process.argv)
+ let operator = process.argv[2]
+ // checking for no operation
+ if (!operator){
+ return "No operation provided..."
+ } 
+ // checking for numbers
+ if (process.argv[3] === undefined){
+ return "No numbers provided..."
+ }
+ // check for other operators that are not plus or minus
+ if (!(operator.includes("plus") || operator.includes('minus'))) {
+ return `Invalid operation: ${operator}`
+ }
+ // for loop: initialize, condition, change
+ let sum = Number(process.argv[3])
+ for (let i = 4; i < process.argv.length; i++) {
+ // plus operation
+ if (operator === "plus") {
+ sum += Number(process.argv[i])
+ } else if (operator === "minus") {
+ sum -= process.argv[i]
+ } 
+ }// end of for loop
+
+ return sum
+ }// end of function
+
+
 
 // Don't change anything below this line.
 module.exports = calculator;