用coffee和socket.io实现的01背包算法

#先说说我为什么写这些吧

当程序猿太苦逼了，真的，时间久了，真没有搬砖的成就感高，好歹人家能盖栋楼（身材也能练得不错），咱们指不定哪天来个熊孩子把硬盘格了就啥也没了。
这学期明显没把心放在前端上......汗啊，将来还想吃着口饭呢，但是这学期绝对没休息，只是忙了很多可能很多人认为无聊的事。
因为这学期无聊事太多了，耽误了很多，也让导师很失望，自己也很自卑，整理一下调调心态。
因为很多是针对作业的奇葩想法，所以，作业嘛，不糊弄就不是作业了，还希望大家多多批评。
兴许因为哪篇文章能解决工作呢。
我想试试Markdown。 #靓照一张 #进入正题 ##后台实现部分:

io = require "socket.io" http = require "http" fs = require "fs" express = require "express" mime = require "mime" app = express()

server = http.createServer app server.listen 8080 console.log "Listening 8080"

app.get "/",(req,res)-> path = "#{__dirname}/console.html" res.writeHead 200,"Content-Type":mime.lookup(path) res.end fs.readFileSync path

app.get "/jquery.min.js",(req,res)-> path = "#{__dirname}/jquery.min.js" res.writeHead 200,"Content-Type":mime.lookup(path) res.end fs.readFileSync path

app.get "/bootstrap.min.js",(req,res)-> path = "#{__dirname}/bootstrap.min.js" res.writeHead 200,"Content-Type":mime.lookup(path) res.end fs.readFileSync path

app.get "/bootstrap.min.css",(req,res)-> path = "#{__dirname}/bootstrap.min.css" res.writeHead 200,"Content-Type":mime.lookup(path) res.end fs.readFileSync path

getCurrentTime = -> d = new Date() return "#{d.getFullYear()}-#{d.getMonth()+1}-#{d.getDate()} #{d.getHours()}:#{d.getMinutes()}:#{d.getSeconds()}"

class dynamicPack pack:(data)-> c=[] i=0 j=0 while i<data.m+1 c[i]=[] c[i][0]=0 i++ while j<data.n+1 c[0][j]=0 j++ i=1 while i<data.m+1 j=1 while j<data.n+1 if data.w[i-1]<=j if c[i-1][j]<c[i-1][j-data.w[i-1]]+data.v[i-1] c[i][j]=c[i-1][j-data.w[i-1]]+data.v[i-1] else c[i][j]=c[i-1][j] else c[i][j] = c[i-1][j] j++ i++ return c; print:(c,data)-> x = [] i = data.m n = data.n str = "" #console.log c[i][m] while i>0 if c[i][n] > c[i-1][n] x[i-1] = 1 n -= data.w[i-1] else x[i-1] = 0 i-- i= 0 count = 0 while i<data.m count += x[i]*data.v[i] str += (i+1)+"," if x[i]!=0 i++ return str+"共计价值#{count}" class knapPack pack : (data)-> @v = data.v @w = data.w @m = data.m @n = data.n @cw = 0 @cv = 0 @put = [] @bestp = 0
```
 	temp_order = 0;
 	temp = 0
 	perp = []
 	i=0
 	while i<@m
 		perp[i] = @v[i]/@w[i] 
 		@put[i] = 0;
 		i++
 	console.log perp
 	i=0
 	while i<@m
 		j=i+1
 		while j<@m
 			if perp[i]<perp[j]
 				temp = @v[i]
 				@v[i] = @v[j]
 				@v[j] = temp

 				temp = @w[i]
 				@w[i] = @w[j]
 				@w[j] = temp
 			j++
 		i++
 backtrack : (i)->
 	console.log i
 	@bound i
 	if i>@m
 		@bestp = @cv
 		return
 	if @cw+@w[i]<=@n
 		@cw+=@w[i]
 		@cv+=@v[i]
 		@put[i]=1
 		@backtrack(i+1)
 		@cw-=@w[i]
 		@cv-=@v[i]
 	if @bound(i+1)>@bestp
 		@backtrack(i+1)
 bound :(i)->
 	leftw = @n - @cw
 	b = @cv
 	while i<=@m and @w[i]<=leftw
 		leftw -= @w[i]
 		b += @v[i]
 		i++
 	b+=@v[i]/@w[i]*leftw if i<@m
 	return b
 print :(data)->
 	@pack(data)
 	console.log @w
 	console.log @v
 	@backtrack(0)
 	console.log @put 
 	return @bestp 
```
dask = (msg)-> answer = "" data = JSON.parse msg console.log data
```
 d = new dynamicPack()
 console.log d.pack(data)
 answer += "动态规划,选择物品"+d.print d.pack(data),data
 return answer
```
kask = (msg)-> answer = "" data = JSON.parse msg console.log data
```
 k = new knapPack()
 answer += "分支限界,最优解"+k.print data
 return answer
```
io.listen(server).on "connection",(socket)-> socket.on "msg",(msg)-> ##console.log msg socket.emit "msg",{time:getCurrentTime(),text:"calculating..."} socket.emit "msg",{time:getCurrentTime(),text:dask(msg)} socket.emit "msg",{time:getCurrentTime(),text:kask(msg)} ##socket.broadcast.emit "msg",data
```
 console.log "#{getCurrentTime()}:Connected"
```

##前端实现部分: <html> <head> <meta charset="utf-8"> <script type="text/javascript" src="./jquery.min.js"></script> <script type="text/javascript" src="./bootstrap.min.js"></script> <script type="text/javascript" src="./socket.io/socket.io.js"></script> <link rel="stylesheet" type="text/css" href="./bootstrap.min.css"> <script type="text/javascript"> $(function(){ var url = window.location.protocol + "//" + window.location.host; var socket = io.connect(url);

     socket.on('connect', function () {
		$("#list").append('<li class="list-group-item">Connected</li>');
		socket.on('msg',function(data){
			$("#list").append($('<li class="list-group-item"></li>').text(data.time+">>"+data.text));
		})
		socket.on('disconnect',function(){
			$("#list").append('<li class="list-group-item">Disconnected</li>');
		})
	})

     $("#chat").keypress(function(e){
     	if (e.which == 13) {
     		e.preventDefault();
     		socket.emit('msg',$("#chat").val());
     		$("#list").append('<li class="list-group-item">'+$('#chat').val()+'</li>');

     		$('#chat').val(" ");
     	};
     })
})
</script>
</head>
<body>
<br>
<div class="container well">
	<ul class="list-group" id="list">
		<li class="list-group-item">输入示例：{"n":10,"m":3,"w":[3,4,5],"v":[4,5,6]}其中n为背包容量，m为物品数量</li>
	</ul>
	<div>
		<input type="text" class="form-control" id="chat">
	</div>
</div>
</body>
</html>

来源：oschina

链接：https://my.oschina.net/u/814846/blog/293129

标签

coffeescript

node

01背包

Socket.IO