// 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 === '/' || num2==='*'){
    operator=num2;
    num2 = 1;
  }

  if(num2==='+' || num2 === '-'){
    operator = num2;
    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';
  }
};