var membersForG20 = [{id:1,countryName:'China',capitalName:'Beijing',used:false},

													 {id:2,countryName:'India',capitalName:'New Delhi',used:false},

													 {id:3,countryName:'European Union',capitalName:'Brussels',used:false},

													 {id:4,countryName:'United States',capitalName:'Washington, DC',used:false},

													 {id:5,countryName:'Indonesia',capitalName:'Jakarta',used:false},

													 {id:6,countryName:'Brazil',capitalName:'Brasilia',used:false}]

			var countryDiv = document.getElementById('countryDiv')

			var capitalDiv = document.getElementById('capitalDiv')

			var video1 = document.getElementById('video1')

			/*

				http://www.w3school.com.cn/tags/av_met_canplaytype.asp

				canPlayType() 方法浏览器是否能播放指定的音频/视频类型。

				canPlayType() 方法可返回下列值之一：

			    "probably" - 浏览器最可能支持该音频/视频类型

			    "maybe" - 浏览器也许支持该音频/视频类型

			    "" - （空字符串）浏览器不支持该音频/视频类型

				实际情况是在Chrome下sfire3.mp4视频无法播放，火狐下提升文件已损坏。

			*/

			console.log(video1.canPlayType('video/mp4; codecs="avc1.42E01E, mp4a.40.2'))//返回probably

			var randomLength = 4

			var matches = 0

			var countrySelected = false

			var selectedCountryIndex

			var selectedCanpitalIndex

			function onSelected(element){

				var id = element.id

				var index

				var type

				id.replace(/(country|canpital)(\d+)/g,function ($0,$1,$2){

					type = $1

					index = $2

				})

				console.log(type+','+index)

				if(type == 'country'  && countrySelected==false){

					countrySelected = true

					selectedCountryIndex = index

				}

				else if(type == 'canpital' && countrySelected==true){

					selectedCanpitalIndex =  index

					if(selectedCountryIndex == selectedCanpitalIndex){

						countrySelected = false

						selectedCountryIndex = -1

						selectedCanpitalIndex = -1

						//matched success

						document.getElementById('country'+index).style.backgroundColor = 'green'

						document.getElementById('canpital'+index).style.backgroundColor = 'green'	

						matches++

						if(matches==randomLength){

							video1.play()

						}

					}

					else{

						//matched error

						document.getElementById('country'+index).style.backgroundColor = 'red'

						document.getElementById('canpital'+index).style.backgroundColor = 'red'	

						countrySelected = false

						selectedCountryIndex = -1

						selectedCanpitalIndex = -1

					}

				}

				else{

				 	//reset Selected

					countrySelected = false

					selectedCountryIndex = -1

					selectedCanpitalIndex = -1

				}

			}

			window.onload = function(){

				var i

				var index

				var member

				var memberLength = membersForG20.length

				var countryElements = []

				var canpitalElements = []

				for(i=0;i<randomLength;i++){

					do{

						index = Math.floor(Math.random()*memberLength)

						member = membersForG20[index]

					}

					while(member.used == true)

					member.used = true

					countryElements.splice(Math.floor(Math.random()*i),0,'<div id='+'"country'+index+'" class="country" onclick="onSelected(this)">'+member.countryName+'</div>')

					canpitalElements.splice(Math.floor(Math.random()*i),0,'<div id='+'"canpital'+index+'" class="canpital" onclick="onSelected(this)">'+member.capitalName+'</div>')

				}

				countryDiv.innerHTML = countryElements.join('')

				capitalDiv.innerHTML = canpitalElements.join('')

			}