Javascript/Date

var s1Btn = document.getElementById("s1Btn");
s1Btn.onclick = function sample1Func(){
  var d = new Date();
  var year = d.getFullYear();
  var month = d.getMonth() + 1;
  var week = d.getDay();
  var day = d.getDate();
  var dayOfTheWeek = [
	"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
  	];
  var hour = d.getHours();
  var minute = d.getMinutes();
  var second = d.getSeconds();
  var today = document.createElement("div");
  today.innerText = year + "年" + month + "月" + day + "日 " + dayOfTheWeek[week];
  s1Btn.after(today);
  var time = document.createElement("div");
  time.innerText = hour + "時" + minute + "分" + second + "秒";
  today.appendChild(time);
	

function s2Func(){
  var s2Start = new Date("2017/07/01");
  var s2Date = new Date();
  var s2GetTime = s2Date.getTime();
  var s2SetTime = s2GetTime - s2Start;
  var s2Diff = Math.floor(s2SetTime / 1000 / 60 / 60 / 24);
  var s2Div = document.getElementById("s2Div");
  s2Div.innerText = "2017年７月１日から" + s2Diff + "日経過";
}
	

function s3Func(){
  var s3End = new Date("2018/07/01");
  var s3Date = new Date();
  var s3GetTime = s3Date.getTime();
  var s3SetTime = s3End - s3GetTime;
  var s3Diff = Math.floor(s3SetTime / 1000 / 60 / 60 / 24);
  var s3Div = document.getElementById("s3Div");
  s3Div.innerText = "2018年７月１日まで" + s3Diff + "日";
}
	

function s4Func(){
  let s4Date = new Date();
  let m;
  let s4Hour; 
  if(s4Date.getHours() >= 12){
  	m = "PM";
  	s4Hour = s4Date.getHours() - 12;
  } else {
  	m = "AM";
  	s4Hour = s4Data.getHours();
  }
  s4Div.innerText = m + s4Hour + "時" + s4Date.getMinutes() + "分" + s4Date.getSeconds() + "秒";
  setTimeout("s4Func()", 1000);
}
	

function s5Func(){
	var d = new Date();
	var nowYear = d.getFullYear();
	var nowMon = d.getMonth() + 1;
	var nowDay = d.getDate();
	var nowWeek = d.getDay();
	var nowHour = d.getHours();
	var nowMin = d.getMinutes();
	var nowSec = d.getSeconds();
	var week = new Array("Sun","Mon","Tue","Wed","Thu","Fri","Sat");
	if(nowMin < 10){
		nowMin = nowMin.toString();
		nowMin = "0" + nowMin;
		console.log(nowMin);
	}
	var nowDate = nowYear + "年" + nowMon + "月" + nowDay + "日("+week[nowWeek]+")";
	var nowTime = nowHour + "時" + nowMin + "分" + nowSec + "秒";
	document.getElementById("s5p").textContent = nowDate + nowTime;
}
setInterval("s5Func()",1000);