function solve(input) {

  let fruit = input.shift();
  let day = input.shift();
  let count = Number(input.shift());

  let weekDay = false;
  let weekEnd = false;
  let isError
  let price = Number;


  if (day === 'monday' || day === 'tuesday' || day === 'wednesday' || day === 'thursday' || day === 'friday') {

    weekDay = true;

  }

  if (day === 'saturday' || day === 'sunday') {

    weekEnd = true;
  }

  if (weekEnd === false && weekDay === false) {

    isError = true;
  }





  switch (fruit) {
    case 'banana':
      if (weekDay === true) {
        price = 2.50;
        console.log((price * count).toFixed(2))

      } if (weekEnd === true) {
        price = 2.70
        console.log((price * count).toFixed(2))
      }

      break;

    case 'apple':
      if (weekDay === true) {

        price = 1.20
        console.log((price * count).toFixed(2))
      } if (weekEnd === true) {

        price = 1.25
        console.log((price * count).toFixed(2))
      }
      break;

    case 'orange':
      if (weekDay === true) {

        price = 0.85
        console.log((price * count).toFixed(2))
      } if (weekEnd === true) {

        price = 0.90
        console.log((price * count).toFixed(2))
      }

      break;

    case 'grapefruit':
      if (weekDay === true) {

        price = 1.45
        console.log((price * count).toFixed(2))
      } if (weekEnd === true) {

        price = 1.60
        console.log((price * count).toFixed(2))
      }

      break;

    case 'kiwi':
      if (weekDay === true) {

        price = 2.70
        console.log((price * count).toFixed(2))
      } if (weekEnd === true) {

        price = 3.00
        console.log((price * count).toFixed(2))
      }

      break;

    case 'grape':
      if (weekDay === true) {

        price = 3.85
        console.log((price * count).toFixed(2))
      } if (weekEnd === true) {

        price = 4.20
        console.log((price * count).toFixed(2))
      }

      break;

    case 'pineapple':
      if (weekDay === true) {
        price = 5.50
        console.log((price * count).toFixed(2))

      } if (weekEnd === true) {

        price = 5.60
        console.log((price * count).toFixed(2))
      }

      break;

  }




}

solve ([ 'orange', 'sunday', '3'])