'use strict'

function main(input) {
  input = input
    .split(' ')
    .map(v => ~~v)
    .sort((a, b) => b - a)
  // .reverse()
  //   console.log(input)

  const ans = input[0] * 10 + input[1] +  input[2]
  console.log(ans)
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'))