0xD34F

$('input').on({
  focus() {
    $(this).val((i, v) => v.replace(', руб.', ''));
  },
  blur() {
    $(this).val((i, v) => v && `${v}, руб.`);
  },
});

const childSelector = 'img';
const className = 'myclass';

$(`.${className}:not(:has(> ${childSelector}))`).removeClass(className);

document.querySelectorAll(`.${className}`).forEach(n => {
  n.classList.toggle(className, !!n.querySelector(`:scope > ${childSelector}`));
});

const elems = document.getElementsByClassName(className);
for (let i = elems.length; i--;) {
  if (!Array.prototype.some.call(elems[i].children, n => n.matches(childSelector))) {
    elems[i].classList.remove(className);
  }
}

reader.onload = function(e) {
  console.log(this.result);
};
reader.readAsText(file);

[...document.getElementsByClassName('cls')].reduce((max, n) => {
  const val = +n.innerText;
  return val > max[1] ? [ n, val ] : max;
}, [ null, -Infinity ])[0].style.color = 'red';

const text = [
  'hello, world!!',
  'fuck the world',
  'fuck everything',
];

$('table').on('click', 'td', function() {
  const $this = $(this);
  const index = (+$this.data('index') + 1) % text.length;

  $this.text(text[index]).data('index', index);
}).find('td').data('index', -1);

function createTree(data, levelKey, childrenKey) {
  const tree = [];

  data.forEach(n => {
    let arr = tree;

    for (let level = 0; n[levelKey] > level++;) {
      arr = arr[arr.length - 1][childrenKey];
    }

    arr.push(Object.assign({ [childrenKey]: [] }, n));
  });

  return tree;
}


const tree = createTree([
  { id: 1, title: 'test1', level: 0 },
  { id: 2, title: 'test2', level: 1 },
  { id: 3, title: 'test3', level: 2 },
  { id: 4, title: 'test4', level: 1 },
  { id: 5, title: 'test5', level: 0 },
], 'level', 'nodes');

$('.calculator_price')
  .find('.calculator_price__item:lt(6)')
  .css('display', 'flex');

$('.calculator_price .calculator_price__item')
  .filter((i, n) => $(n).index() < 6)
  .css('display', 'flex');

document.querySelectorAll('.calculator_price').forEach(n => {
  [...n.querySelectorAll('.calculator_price__item')]
    .slice(0, 6)
    .forEach(n => n.style.display = 'flex');
});

<div id="inputs">
  <input maxlength="5">
</div>

const $inputs = $('#inputs').on('input', 'input', function() {
  const $this = $(this);
  const maxlen = +$this.attr('maxlength');

  if ($this.val().length === maxlen) {
    let $next = $this.next();
    if (!$next.length) {
      $next = $(`<input maxlength="${maxlen}">`).appendTo($inputs);
    }

    $next.focus();
  }
});

// или

document.querySelector('#inputs').addEventListener('input', function(e) {
  const input = e.target;
  const maxlen = +input.getAttribute('maxlength');

  if (input.value.length === maxlen) {
    if (!input.nextElementSibling) {
      this.insertAdjacentHTML('beforeend', `<input maxlength="${maxlen}">`);
    }

    input.nextElementSibling.focus();
  }
});

div.classList.remove(...[...div.classList].filter(n => n.indexOf('_key-word') !== -1))

Владивосток - плюс 7 часов к текущему.

function getTimeInTimezone(zone) {
  const
    d = new Date(),
    utc = d.getTime() + d.getTimezoneOffset() * 60000;

  return new Date(utc + zone * 3600000);
}

(function(w) {
  'use strict';
  w.Test = function(hello) {
    console.log(hello);
  };
}(window));

var Test = (function() {
  'use strict';
  return function(hello) {
    console.log(hello);
  };
}());

(function() {
  Test = function(hello) {
    console.log(hello);
  };
}());

if (![ 'search', 'search_input', 'cancel_btn' ].includes(target.className)) {

const t = target.className;
if (t !== 'search' && t !== 'search_input' && t !== 'cancel_btn') {

if (!target.matches('.search, .search_input, .cancel_btn')) {

<div class="block">hello, world!!</div>
<div class="block">fuck the world</div>
<div class="block">fuck everything</div>

.block {
  display: inline-block;
  width: 500px;
  height: 150px;
  padding: 20px;
  background: red;
  color: white;
}

const $blocks = $('.block').hide();
let i = -1;

(function showNext() {
  $blocks
    .eq(i = (i + 1) % $blocks.length)
    .dequeue()
    .fadeIn(1000)
    .delay(500)
    .fadeOut(1000)
    .queue(showNext);
})();

|о|д|и|н|
|е|т|ы|д|
|ч|е|р|в|
|и|р|т|а|

function makeTable(data) {
  data = data.join('').split('');

  let width = Math.sqrt(data.length) | 0;
  let height = (data.length / width) | 0;

  while (width * height !== data.length) {
    width--;
    height = (data.length / width) | 0;
  }

  const position = [ 0, 0 ];
  const directions = [
    [  1,  0 ],
    [  0,  1 ],
    [ -1,  0 ],
    [  0, -1 ],
  ];
  let direction = 0;

  const result = Array.from({ length: height }, n => Array(width).fill(null));

  for (const n of data) {
    result[position[1]][position[0]] = n;

    if (null !== (result[position[1] + directions[direction][1]] || {})[position[0] + directions[direction][0]]) {
      direction = (direction + 1) % directions.length;
    }

    position[0] += directions[direction][0];
    position[1] += directions[direction][1];
  }

  return result.map(n => n.join(' ')).join('\n');
}

console.log(makeTable([ 'раз', 'два', 'три' ])); /*
р а з
р и д
т а в
*/
console.log(makeTable([ 'один', 'два', 'три', 'четыре' ])); /*
о д и н
е т ы д
ч е р в
и р т а
*/
console.log(makeTable([ 'hello', ',', ' ', 'world', '!!' ])); /*
h e
! l
! l
d o
l ,
r  
o w
*/