'use strict';

function main(input) {
  let inputs = input.split('\n').map(num => parseInt(num, 10));
  inputs.shift();
  let uniq_diameter = inputs.filter((num, i) => inputs.indexOf(num) === i);
  console.log(uniq_diameter.length);
}

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