// EXERCISE 2

	// // extend our awesome calc function by adding some conditions...
	// // in case the third arguments is  / or * and the second argument is not provided, the second argument should default to one.
	// // in case the third arguments is +  or  - and the second argument is not provided, the second argument should default to zero.

	// //Example:

	// calc(10,"/")  //10
	// calc (30,"*") //30
	// calc (2,"+")  //2
	// calc (3,"-")  //3


	function calc (num1, num2, operator) {

		if(!num2 && operator === '/' || operator === '*'){

			num2 = 1;

		}

		if(!num2 && operator === '+'|| operator === '-'){

			num2 = 0;

		}

		if (operator === '+') {

			return num1 + num2;

		} else if (operator === '-') {

			return num1 - num2;

		} else if (operator === '*') {

			return num1 * num2;

		} else if (operator === '/') {

			return num1 / num2;

		} else {

			return 'wrong data provided';
		}
	};

	module.exports = {
		calc
	}