Calculating with Functions - Codewars Kata

Calculating with Functions.js

function zero(param) { return (!param) ? 0 : param(0); } // param = plus / minus ...
function one(param) { return (!param) ? 1 : param(1); }
function two(param) { return (!param) ? 2 : param(2); }
function three(param) { return (!param) ? 3 : param(3); }
function four(param) { return (!param) ? 4 : param(4); }
function five(param) { return (!param) ? 5 : param(5); }
function six(param) { return (!param) ? 6 : param(6); }
function seven(param) { return (!param) ? 7 : param(7); }
function eight(param) { return (!param) ? 8 : param(8); }
function nine(param) { return (!param) ? 9 : param(9); }

function plus(inicial_num) {
  return function (final_num) {
    return inicial_num + final_num;
  }
}
function minus(inicial_num) {
  return function (final_num) {
    return final_num - inicial_num;
  }
}
function times(inicial_num) {
  return function (final_num) {
    return inicial_num * final_num;
  }
}
function dividedBy(inicial_num) {
  return function (final_num) {
    return parseInt(final_num / inicial_num);
  }
}