$(document).ready(function(){

  var totalslides = $('p').length;
  var currentslide;
  var newslide;

  $('.left').on('click', function() {
    currentslide = $('p.active').index()+1;
    if (currentslide == 1){
      newslide = totalslides;
    }
    else {
      newslide = currentslide-1;
    }
    $('p.active').removeClass('active');
    $('p:nth-child('+newslide+')').addClass('active');
  });

  $('.right').on('click', function() {
    currentslide = $('.slide.active').index()+1;
    if (currentslide == totalslides){
      newslide = 1;
    }
    else {
      newslide = currentslide+1;
    }
    $('p.active').removeClass('active');
    $('p:nth-child('+newslide+')').addClass('active');
  });

});