function main(input) {
  const args = input.split(' ');
  const N = parseInt(args[0], 10);
  
  if (N % 2 == 0) {
    console.log(N / 2);
  } else {
    console.log(Math.ceil(N / 2));
  }
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));