php多线程pthreads的安装与使用
安装Pthreads 基本上需要重新编译PHP,加上 --enable-maintainer-zts 参数,但是用这个文档很少;bug会很多很有很多意想不到的问题,生成环境上只能呵呵了,所以这个东西玩玩就算了,真正多线程还是用Python、C等等
以下代码大部分来自网络
一、安装
这里使用的是 php-7.0.2
./configure \
--prefix=/usr/local/php7 \
--with-config-file-path=/etc \
--with-config-file-scan-dir=/etc/php.d \
--enable-debug \
--enable-maintainer-zts \
--enable-pcntl \
--enable-fpm \
--enable-opcache \
--enable-embed=shared \
--enable-json=shared \
--enable-phpdbg \
--with-curl=shared \
--with-mysql=/usr/local/mysql \
--with-mysqli=/usr/local/mysql/bin/mysql_config \
--with-pdo-mysql make && make install
安装pthreads
pecl install pthreads
二、Thread
<?php
#1
$thread = new class extends Thread {
public function run() {
echo "Hello World {$this->getThreadId()}\n";
}
}; $thread->start() && $thread->join(); #2 class workerThread extends Thread {
public function __construct($i){
$this->i=$i;
} public function run(){
while(true){
echo $this->i."\n";
sleep(1);
}
}
} for($i=0;$i<50;$i++){
$workers[$i]=new workerThread($i);
$workers[$i]->start();
} ?>
三、 Worker 与 Stackable
Stackables are tasks that are executed by Worker threads. You can synchronize with, read, and write Stackable objects before, after and during their execution.
<?php
class SQLQuery extends Stackable { public function __construct($sql) {
$this->sql = $sql;
} public function run() {
$dbh = $this->worker->getConnection();
$row = $dbh->query($this->sql);
while($member = $row->fetch(PDO::FETCH_ASSOC)){
print_r($member);
}
} } class ExampleWorker extends Worker {
public static $dbh;
public function __construct($name) {
} public function run(){
self::$dbh = new PDO('mysql:host=10.0.0.30;dbname=testdb','root','123456');
}
public function getConnection(){
return self::$dbh;
}
} $worker = new ExampleWorker("My Worker Thread"); $sql1 = new SQLQuery('select * from test order by id desc limit 1,5');
$worker->stack($sql1); $sql2 = new SQLQuery('select * from test order by id desc limit 5,5');
$worker->stack($sql2); $worker->start();
$worker->shutdown();
?>
四、 互斥锁
什么情况下会用到互斥锁?在你需要控制多个线程同一时刻只能有一个线程工作的情况下可以使用。一个简单的计数器程序,说明有无互斥锁情况下的不同
<?php
$counter = 0;
$handle=fopen("/tmp/counter.txt", "w");
fwrite($handle, $counter );
fclose($handle); class CounterThread extends Thread {
public function __construct($mutex = null){
$this->mutex = $mutex;
$this->handle = fopen("/tmp/counter.txt", "w+");
}
public function __destruct(){
fclose($this->handle);
}
public function run() {
if($this->mutex)
$locked=Mutex::lock($this->mutex); $counter = intval(fgets($this->handle));
$counter++;
rewind($this->handle);
fputs($this->handle, $counter );
printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter); if($this->mutex)
Mutex::unlock($this->mutex);
}
} //没有互斥锁
for ($i=0;$i<50;$i++){
$threads[$i] = new CounterThread();
$threads[$i]->start(); } //加入互斥锁
$mutex = Mutex::create(true);
for ($i=0;$i<50;$i++){
$threads[$i] = new CounterThread($mutex);
$threads[$i]->start(); } Mutex::unlock($mutex);
for ($i=0;$i<50;$i++){
$threads[$i]->join();
}
Mutex::destroy($mutex); ?>
多线程与共享内存
在共享内存的例子中,没有使用任何锁,仍然可能正常工作,可能工作内存操作本身具备锁的功能
<?php
$tmp = tempnam(__FILE__, 'PHP');
$key = ftok($tmp, 'a'); $shmid = shm_attach($key);
$counter = 0;
shm_put_var( $shmid, 1, $counter ); class CounterThread extends Thread {
public function __construct($shmid){
$this->shmid = $shmid;
}
public function run() { $counter = shm_get_var( $this->shmid, 1 );
$counter++;
shm_put_var( $this->shmid, 1, $counter ); printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter);
}
} for ($i=0;$i<100;$i++){
$threads[] = new CounterThread($shmid);
}
for ($i=0;$i<100;$i++){
$threads[$i]->start(); } for ($i=0;$i<100;$i++){
$threads[$i]->join();
}
shm_remove( $shmid );
shm_detach( $shmid );
?>
五、 线程同步
有些场景我们不希望 thread->start() 就开始运行程序,而是希望线程等待我们的命令。$thread->wait();测作用是 thread->start()后线程并不会立即运行,只有收到 $thread->notify(); 发出的信号后才运行
<?php
$tmp = tempnam(__FILE__, 'PHP');
$key = ftok($tmp, 'a'); $shmid = shm_attach($key);
$counter = 0;
shm_put_var( $shmid, 1, $counter ); class CounterThread extends Thread {
public function __construct($shmid){
$this->shmid = $shmid;
}
public function run() { $this->synchronized(function($thread){
$thread->wait();
}, $this); $counter = shm_get_var( $this->shmid, 1 );
$counter++;
shm_put_var( $this->shmid, 1, $counter ); printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter);
}
} for ($i=0;$i<100;$i++){
$threads[] = new CounterThread($shmid);
}
for ($i=0;$i<100;$i++){
$threads[$i]->start(); } for ($i=0;$i<100;$i++){
$threads[$i]->synchronized(function($thread){
$thread->notify();
}, $threads[$i]);
} for ($i=0;$i<100;$i++){
$threads[$i]->join();
}
shm_remove( $shmid );
shm_detach( $shmid );
?>
六、线程池
一个Pool类
<?php
class Update extends Thread { public $running = false;
public $row = array();
public function __construct($row) { $this->row = $row;
$this->sql = null;
} public function run() { if(strlen($this->row['bankno']) > 100 ){
$bankno = safenet_decrypt($this->row['bankno']);
}else{
$error = sprintf("%s, %s\r\n",$this->row['id'], $this->row['bankno']);
file_put_contents("bankno_error.log", $error, FILE_APPEND);
} if( strlen($bankno) > 7 ){
$sql = sprintf("update members set bankno = '%s' where id = '%s';", $bankno, $this->row['id']); $this->sql = $sql;
} printf("%s\n",$this->sql);
} } class Pool {
public $pool = array();
public function __construct($count) {
$this->count = $count;
}
public function push($row){
if(count($this->pool) < $this->count){
$this->pool[] = new Update($row);
return true;
}else{
return false;
}
}
public function start(){
foreach ( $this->pool as $id => $worker){
$this->pool[$id]->start();
}
}
public function join(){
foreach ( $this->pool as $id => $worker){
$this->pool[$id]->join();
}
}
public function clean(){
foreach ( $this->pool as $id => $worker){
if(! $worker->isRunning()){
unset($this->pool[$id]);
}
}
}
} try {
$dbh = new PDO("mysql:host=" . str_replace(':', ';port=', $dbhost) . ";dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true
)
); $sql = "select id,bankno from members order by id desc";
$row = $dbh->query($sql);
$pool = new Pool(5);
while($member = $row->fetch(PDO::FETCH_ASSOC))
{ while(true){
if($pool->push($member)){ //压入任务到池中
break;
}else{ //如果池已经满,就开始启动线程
$pool->start();
$pool->join();
$pool->clean();
}
}
}
$pool->start();
$pool->join(); $dbh = null; } catch (Exception $e) {
echo '[' , date('H:i:s') , ']', '系统错误', $e->getMessage(), "\n";
}
?>
动态队列线程池
上面的例子是当线程池满后执行start统一启动,下面的例子是只要线程池中有空闲便立即创建新线程。
<?php
class Update extends Thread { public $running = false;
public $row = array();
public function __construct($row) { $this->row = $row;
$this->sql = null;
//print_r($this->row);
} public function run() { if(strlen($this->row['bankno']) > 100 ){
$bankno = safenet_decrypt($this->row['bankno']);
}else{
$error = sprintf("%s, %s\r\n",$this->row['id'], $this->row['bankno']);
file_put_contents("bankno_error.log", $error, FILE_APPEND);
} if( strlen($bankno) > 7 ){
$sql = sprintf("update members set bankno = '%s' where id = '%s';", $bankno, $this->row['id']); $this->sql = $sql;
} printf("%s\n",$this->sql);
} } try {
$dbh = new PDO("mysql:host=" . str_replace(':', ';port=', $dbhost) . ";dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true
)
); $sql = "select id,bankno from members order by id desc limit 50"; $row = $dbh->query($sql);
$pool = array();
while($member = $row->fetch(PDO::FETCH_ASSOC))
{
$id = $member['id'];
while (true){
if(count($pool) < 5){
$pool[$id] = new Update($member);
$pool[$id]->start();
break;
}else{
foreach ( $pool as $name => $worker){
if(! $worker->isRunning()){
unset($pool[$name]);
}
}
}
} } $dbh = null; } catch (Exception $e) {
echo '【' , date('H:i:s') , '】', '【系统错误】', $e->getMessage(), "\n";
}
?>
pthreads Pool类
<?php class WebWorker extends Worker { public function __construct(SafeLog $logger) {
$this->logger = $logger;
} protected $loger;
} class WebWork extends Stackable { public function isComplete() {
return $this->complete;
} public function run() {
$this->worker
->logger
->log("%s executing in Thread #%lu",
__CLASS__, $this->worker->getThreadId());
$this->complete = true;
} protected $complete;
} class SafeLog extends Stackable { protected function log($message, $args = []) {
$args = func_get_args(); if (($message = array_shift($args))) {
echo vsprintf(
"{$message}\n", $args);
}
}
} $pool = new Pool(8, \WebWorker::class, [new SafeLog()]); $pool->submit($w=new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->shutdown(); $pool->collect(function($work){
return $work->isComplete();
}); var_dump($pool);
七、多线程文件安全读写
LOCK_SH 取得共享锁定(读取的程序)
LOCK_EX 取得独占锁定(写入的程序
LOCK_UN 释放锁定(无论共享或独占)
LOCK_NB 如果不希望 flock() 在锁定时堵塞
<?php $fp = fopen("/tmp/lock.txt", "r+");
if (flock($fp, LOCK_EX)) { // 进行排它型锁定
ftruncate($fp, 0); // truncate file
fwrite($fp, "Write something here\n");
fflush($fp); // flush output before releasing the lock
flock($fp, LOCK_UN); // 释放锁定
} else {
echo "Couldn't get the lock!";
}
fclose($fp); $fp = fopen('/tmp/lock.txt', 'r+');
if(!flock($fp, LOCK_EX | LOCK_NB)) {
echo 'Unable to obtain lock';
exit(-1);
}
fclose($fp);
?>
八、多线程与数据连接
pthreads 与 pdo 同时使用是,需要注意一点,需要静态声明public static $dbh;并且通过单例模式访问数据库连接。
Worker 与 PDO
<?php
class Work extends Stackable { public function __construct() {
} public function run() {
$dbh = $this->worker->getConnection();
$sql = "select id,name from members order by id desc limit 50";
$row = $dbh->query($sql);
while($member = $row->fetch(PDO::FETCH_ASSOC)){
print_r($member);
}
} } class ExampleWorker extends Worker {
public static $dbh;
public function __construct($name) {
} /*
* The run method should just prepare the environment for the work that is coming ...
*/
public function run(){
self::$dbh = new PDO('mysql:host=192.168.2.1;dbname=example','www','123456');
}
public function getConnection(){
return self::$dbh;
}
} $worker = new ExampleWorker("My Worker Thread"); $work=new Work();
$worker->stack($work); $worker->start();
$worker->shutdown();
?>
Pool 与 PDO
在线程池中链接数据库
# cat pool.php
<?php
class ExampleWorker extends Worker { public function __construct(Logging $logger) {
$this->logger = $logger;
} protected $logger;
} /* the collectable class implements machinery for Pool::collect */
class Work extends Stackable {
public function __construct($number) {
$this->number = $number;
}
public function run() {
$dbhost = 'db.example.com'; // 数据库服务器
$dbuser = 'example.com'; // 数据库用户名
$dbpw = 'password'; // 数据库密码
$dbname = 'example_real';
$dbh = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true,
PDO::ATTR_PERSISTENT => true
)
);
$sql = "select OPEN_TIME, `COMMENT` from MT4_TRADES where LOGIN='".$this->number['name']."' and CMD='6' and `COMMENT` = '".$this->number['order'].":DEPOSIT'";
#echo $sql;
$row = $dbh->query($sql);
$mt4_trades = $row->fetch(PDO::FETCH_ASSOC);
if($mt4_trades){ $row = null; $sql = "UPDATE db_example.accounts SET paystatus='成功', deposit_time='".$mt4_trades['OPEN_TIME']."' where `order` = '".$this->number['order']."';";
$dbh->query($sql);
#printf("%s\n",$sql);
}
$dbh = null;
printf("runtime: %s, %s, %s\n", date('Y-m-d H:i:s'), $this->worker->getThreadId() ,$this->number['order']); }
} class Logging extends Stackable {
protected static $dbh;
public function __construct() {
$dbhost = 'db.example.com'; // 数据库服务器
$dbuser = 'example.com'; // 数据库用户名
$dbpw = 'password'; // 数据库密码
$dbname = 'example_real'; // 数据库名 self::$dbh = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true
)
); }
protected function log($message, $args = []) {
$args = func_get_args(); if (($message = array_shift($args))) {
echo vsprintf("{$message}\n", $args);
}
} protected function getConnection(){
return self::$dbh;
}
} $pool = new Pool(200, \ExampleWorker::class, [new Logging()]); $dbhost = 'db.example.com'; // 数据库服务器
$dbuser = 'example.com'; // 数据库用户名
$dbpw = 'password'; // 数据库密码
$dbname = 'db_example';
$dbh = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true
)
);
$sql = "select `order`,name from accounts where deposit_time is null order by id desc"; $row = $dbh->query($sql);
while($account = $row->fetch(PDO::FETCH_ASSOC))
{
$pool->submit(new Work($account));
} $pool->shutdown(); ?>
进一步改进上面程序,我们使用单例模式 $this->worker->getInstance(); 全局仅仅做一次数据库连接,线程使用共享的数据库连接
<?php
class ExampleWorker extends Worker { #public function __construct(Logging $logger) {
# $this->logger = $logger;
#} #protected $logger;
protected static $dbh;
public function __construct() { }
public function run(){
$dbhost = 'db.example.com'; // 数据库服务器
$dbuser = 'example.com'; // 数据库用户名
$dbpw = 'password'; // 数据库密码
$dbname = 'example'; // 数据库名 self::$dbh = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true,
PDO::ATTR_PERSISTENT => true
)
); }
protected function getInstance(){
return self::$dbh;
} } /* the collectable class implements machinery for Pool::collect */
class Work extends Stackable {
public function __construct($data) {
$this->data = $data;
#print_r($data);
} public function run() {
#$this->worker->logger->log("%s executing in Thread #%lu", __CLASS__, $this->worker->getThreadId() ); try {
$dbh = $this->worker->getInstance();
#print_r($dbh);
$id = $this->data['id'];
$mobile = safenet_decrypt($this->data['mobile']);
#printf("%d, %s \n", $id, $mobile);
if(strlen($mobile) > 11){
$mobile = substr($mobile, -11);
}
if($mobile == 'null'){
# $sql = "UPDATE members_digest SET mobile = '".$mobile."' where id = '".$id."'";
# printf("%s\n",$sql);
# $dbh->query($sql);
$mobile = '';
$sql = "UPDATE members_digest SET mobile = :mobile where id = :id";
}else{
$sql = "UPDATE members_digest SET mobile = md5(:mobile) where id = :id";
}
$sth = $dbh->prepare($sql);
$sth->bindValue(':mobile', $mobile);
$sth->bindValue(':id', $id);
$sth->execute();
#echo $sth->debugDumpParams();
}
catch(PDOException $e) {
$error = sprintf("%s,%s\n", $mobile, $id );
file_put_contents("mobile_error.log", $error, FILE_APPEND);
} #$dbh = null;
printf("runtime: %s, %s, %s, %s\n", date('Y-m-d H:i:s'), $this->worker->getThreadId() ,$mobile, $id);
#printf("runtime: %s, %s\n", date('Y-m-d H:i:s'), $this->number);
}
} $pool = new Pool(100, \ExampleWorker::class, []); #foreach (range(0, 100) as $number) {
# $pool->submit(new Work($number));
#} $dbhost = 'db.example.com'; // 数据库服务器
$dbuser = 'example.com'; // 数据库用户名
$dbpw = 'password'; // 数据库密码
$dbname = 'example';
$dbh = new PDO("mysql:host=$dbhost;port=3307;dbname=$dbname", $dbuser, $dbpw, array(
PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'',
PDO::MYSQL_ATTR_COMPRESS => true
)
);
#print_r($dbh); #$sql = "select id, mobile from members where id < :id";
#$sth = $dbh->prepare($sql);
#$sth->bindValue(':id',300);
#$sth->execute();
#$result = $sth->fetchAll();
#print_r($result);
#
#$sql = "UPDATE members_digest SET mobile = :mobile where id = :id";
#$sth = $dbh->prepare($sql);
#$sth->bindValue(':mobile', 'aa');
#$sth->bindValue(':id','272');
#echo $sth->execute();
#echo $sth->queryString;
#echo $sth->debugDumpParams(); $sql = "select id, mobile from members order by id asc"; // limit 1000";
$row = $dbh->query($sql);
while($members = $row->fetch(PDO::FETCH_ASSOC))
{
#$order = $account['order'];
#printf("%s\n",$order);
//print_r($members);
$pool->submit(new Work($members));
#unset($account['order']);
} $pool->shutdown(); ?>
多线程中操作数据库总结
总的来说 pthreads 仍然处在发展中,仍有一些不足的地方,我们也可以看到pthreads的git在不断改进这个项目
数据库持久链接很重要,否则每个线程都会开启一次数据库连接,然后关闭,会导致很多链接超时。
<?php
$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass, array(
PDO::ATTR_PERSISTENT => true
));
?>
php多线程pthreads的安装与使用的更多相关文章
- Windows下PHP多线程扩展pthreads的安装
pthreads扩展安装步骤 1.查看phpinfo() 获取PHP版本号及位数(x86表示32位,x64表示64位).编译器版本.PHP配置文件加载所在位置等.如下图所示: 2.pthreads扩展 ...
- PHP多线程pthreads
Home | 简体中文 | 繁体中文 | 杂文 | Search | ITEYE 博客 | OSChina 博客 | Facebook | Linkedin | 作品与服务 | EmailPHP 高级 ...
- centos7 安装php 多线程pthreads
第一步:yum源更新 yum update 第二步:下载php7源码 wget http://124.202.164.8/files/312100000A0BB72D/cn.php.net/distr ...
- ***PHP多线程pthreads 实现QQ号码爬虫
通过空间历史浏览,爬出查看你空间的人(一般限制20人,除非开通黄钻),然后在爬出这20人的浏览记录,依次向下爬,你可以控制爬行深度.这里仅仅给出怕中代码片段,你可以进一步优化,将QQ分类存储.通过QQ ...
- windows下安装php真正的多线程扩展pthreads教程
扩展地址:http://docs.php.net/manual/zh/book.pthreads.php 注意事项php5.3或以上,且为线程安全版本.apache和php使用的编译器必须一致.通过p ...
- linux下编译安装pthreads扩展
这里讲的是如何编译安装pthreads,以后编译安装其他PHP扩展可以参考此方法. 下载pthreads源码:http://pecl.php.net/package/pthreads 首先确定安装的p ...
- LNAMP服务器环境(源码安装)
在安装前先看下它们安装时所需要的依赖库:http://www.cnblogs.com/fps2tao/p/7699448.html 1.nginx源码安装 下载:http://nginx.org/en ...
- 如何在Mac OSX上安装xgboost
听说xgboost效果很不错,于是准备学习下,但是发现大多数资料都是在讲如何在windows或linux下安装xgboost,而且照着官方文档也没有正确的安装好多线程的xgboost.最后还是从the ...
- Linux 多线程下载工具:axel
wget 应该是最常用的下载工具了,但是其不支持多线程下载. axel 安装 epel 源有 axel 的二进制包,可以使用 yum 安装. yum install epel-release yum ...
随机推荐
- ASP.NET MVC和WebForm 轻松实现前端和后端的双重验证 jquery.validate+ValidationSugar
上次不足的改进 可能上一个贴子给大家带来很多误解,所以我这次把DEMO完善了两个版本 [ASP.NET WEBFROM]和[ ASP.NET MVC] 修改了一些BUG,并且修改了一些细了 在上个贴子 ...
- CSS3的变形transform、过渡transition、动画animation学习
学习CSS3动画animation得先了解一些关于变形transform.过渡transition的知识 这些新属性大多在新版浏览器得到了支持,有些需要添加浏览器前缀(-webkit-.-moz-.- ...
- 组合数学 - 母函数的运用 + 模板 --- hdu : 2082
找单词 Time Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submiss ...
- weblogic 12C 数据源配置出错的解决办法
驱动程序类名称: 11G 10.3.6与12G数据源配置有很大区别,整个一天才搞明白. 如有疑问可留言:http://www.cnblogs.com/endv/p/4110798.html 配 ...
- 设计模式--中介(Mediator)模式
时隔很长一段时,现在又重温设计模式,上个星期学习<设计模式--代理(Proxy)模式>http://www.cnblogs.com/insus/p/4128814.html. 温故而知新, ...
- jquery实现全选功能
主要是模拟一些网页中的表格实现全选功能. <form> 你爱好的运动是: <input type="checkbox" id="Check" ...
- 回文串---吉哥系列故事——完美队形II
HDU 4513 Problem Description 吉哥又想出了一个新的完美队形游戏! 假设有n个人按顺序站在他的面前,他们的身高分别是h[1], h[2] ... h[n],吉哥希望从中挑出 ...
- C# on Visual Studio Code
installation Download .NET Core SDK installer and install it. https://www.microsoft.com/net/download ...
- [下载] MultiBeast 6.2.1版,支持10.9 Mavericks。Mac上的驱动精灵,最简单安装驱动的方式。
下载地址1:http://pan.baidu.com/s/1i3ier9F 下载地址2:http://www.tonymacx86.com/downloads.php?do=cat&id=3 ...
- NYOJ 42 一笔画问题
一笔画问题 时间限制:3000 ms | 内存限制:65535 KB 难度:4 描述 zyc从小就比较喜欢玩一些小游戏,其中就包括画一笔画,他想请你帮他写一个程序,判断一个图是否能够用一笔画下 ...