'use strict'

function main(input) {
  input = input.trim().split('\n')
  const n = input[0]
  const nums = input[1]
    .split(' ')
    .map(v => parseFloat(v))
    .sort((a, b) => a - b)
    .reduce((a, b) => {
      return (a + b) / 2
    })

  console.log(nums)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'))
