下面是版本信息： mesos version : mesos-0.25.0-0.2.70.centos701406.x86_64 marathon version : marathon-0.11.1-1.0.432.el7.x86_64 chronos version : chronos-2.4.0-0.1.20151007110204.el7.x86_64 zookeeper version: mesosphere-zookeeper-3.4.6-0.1.20141204175332.centos7.x86_64 我通过下面命令在 Centos7上装了mesos,zookeeper,marathon等. sudo rpm -Uvh http://repos.mesosphere.io/el/7/noarch/RPMS/mesosphere-el-repo-7-1.noarch.rpm sudo yum install mesos marathon chronos mesosphere-zookeeper 我配置了2个master, ip分别是192.168.253.129 and 192.168.253.130.我也在 [/etc/marathon/conf]目录下创建了master,zk,hostname文件.下面是这3个文件的详情 1.master>>zk://192.168.253.129:2181,192.168.253.130:2181/mesos 2.zk>>zk://192.168.253.129:2181,192.168.253.130:2181/marathon 3.hostname>>192.168.253.129 启动mesoso-master服务之后，我可以访问 url [http://192.168.253.129:5050] and http://192.168.253.130:5050,并且看到leader master被成功选举出来. 但是却无法打开marathon的url[http://192.168.253.129:8080]。 下面是我 [service marathon status -l] 我查看marathon的状态 +++++++++++++++++++++++++++++++++++++++++++++++++++++#localhost]# service marathon status -l Redirecting to /bin/systemctl status -l marathon.service marathon.service - Marathon Loaded: loaded (/usr/lib/systemd/system/marathon.service; enabled) Active: activating (auto-restart) (Result: exit-code) since Sun 2015-10-25 03:03:44 PDT; 1s ago Process: 6777 ExecStart=/usr/bin/marathon (code=exited, status=1/FAILURE) Main PID: 6777 (code=exited, status=1/FAILURE) Oct 25 03:03:44 develop-mesos-master1 #localhost.localdomain systemd[1]: marathon.service: main process exited, code=exited, status=1/FAILURE Oct 25 03:03:44 develop-mesos-master1 #localhost.localdomain systemd[1]: Unit marathon.service entered failed state. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 下面是我用命令 [journalctl -o verbose _PID=6777] 查看marathon进程的详细信息。 +++++++++++++++++++++++++++++++++++++++++++++++++++++ #localhost conf]# journalctl -o verbose _PID=6777 -- Logs begin at Sun 2015-10-25 02:48:41 PDT, end at Sun 2015-10-25 03:18:55 PDT. -- Sun 2015-10-25 03:03:44.168930 PDT [s=5827ad02b7164cdeb1947da2c9a80cc6;i=208c;b=8cdffcc7c1c849b887266e94d8cbe621;m=36175ff3;t=522eaf5bed3e2; PRIORITY=6 _UID=0 _GID=0 _SYSTEMD_SLICE=system.slice _BOOT_ID=8cdffcc7c1c849b887266e94d8cbe621 _MACHINE_ID=e485efeafe934ce99407be78a4ed3aac SYSLOG_FACILITY=3 _CAP_EFFECTIVE=1fffffffff _TRANSPORT=stdout _EXE=/usr/bin/bash _HOSTNAME=develop-mesos-master1 #localhost.localdomain SYSLOG_IDENTIFIER=marathon MESSAGE=run_jar --master zk://192.168.253.129:2181,192.168.253.130:2181/mesos --zk zk://192.168.253.129:2181,192.168.253.130:2181/marath _COMM=marathon _CMDLINE=/bin/bash /usr/bin/marathon _SYSTEMD_CGROUP=/system.slice/marathon.service _SYSTEMD_UNIT=marathon.service _PID=6777 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 有高手能给解答一下吗？

<div class="post-text" itemprop="text"> <p>I'm running a php docker image (php:5.6-apache) which has apache's error and access logs redirected to STDERR and STDOUT respectively using symbolic links.</p> <p>When I run the docker image in the foreground or access the docker container logs, I can see the STDOUT output. But I don't see any errors (even when I generate php errors).</p> <p>Any idea why that is and how I can fix it?</p> <p>I'm running docker for Mac (but I don't think this makes any difference)</p> <p>Thanks</p> <pre><code>access.log -&gt; /dev/stdout error.log -&gt; /dev/stderr other_vhosts_access.log -&gt; /dev/stdout </code></pre> <p><strong>Edit / Solved:</strong> As @BMitch mentions and proves below, the STDERR redirection works fine. The problem was with PHP configuration. If I logged an error with <code>error_log()</code>, it would get output to the log. But if I had a php error, like calling an undefined function, the error would never appear in the log. This seems a little inconsistent. In any case, ...</p> <p>I had to create a <code>php.ini</code> file in <code>/usr/local/etc/php/</code> and add these two parameters:</p> <pre><code>log_errors = On error_log = /var/log/apache2/error.log </code></pre> <p>and then restart the docker container. This caused all PHP errors to be logged and output to STDERR. See @German's answer for an example.</p> </div>

when i start a docker containner on mesos-slave the mesos-slave log shows that: ``` I1223 15:38:40.822557 258486272 docker.cpp:761] Starting container 'ea1ed2fa-c2e3-469a-bcc4-142e0a6c624d' for task '2-1.2fb839ea-a948-11e5-9c42-2e7bf2aa25a6' (and executor '2-1.2fb839ea-a948-11e5-9c42-2e7bf2aa25a6') of framework '13165a00-8e58-4d80-b84d-fe4652022a3e-0000' E1223 15:38:41.219044 254730240 slave.cpp:3342] Container 'ea1ed2fa-c2e3-469a-bcc4-142e0a6c624d' for executor '2-1.2fb839ea-a948-11e5-9c42-2e7bf2aa25a6' of framework '13165a00-8e58-4d80-b84d-fe4652022a3e-0000' failed to start: Failed to 'docker -H unix:///var/run/docker.sock pull python:3': exit status = exited with status 1 stderr = An error occurred trying to connect: Post https:///var/run/docker.sock/v1.19/images/create?fromImage=python%3A3: dial unix /var/run/docker.sock: no such file or directory ``` from that, i can see mesos-slave excute docker -H unix:///var/run/docker.sock pull python:3 to download images. but I use Mac OSX, And the docker is running in the vm , So there is no docker.sock file in my slave but the vm. How cuold i solve the issue on Mac OSX? please help me ,thanks!

在marathon项目中，上传的app如下图， 效果就是，先在本地下载一个war包，和tomcat的压缩包，在解压压缩包，然后将war包放到tomcat／webapp目录下，再将端口号改成8001，最后再启动tomcat  对此，我有一些疑问，请教一下大家，  如上图， job开始running后，marathon将需要的file都下载到了当前task的log的存放地址下，但是我新增app的时候输入的conmand，并没有 cd 到 log的路径，所以应该是marathon在后台，默认给command添加了 cd log_dir的shell ， 但是 在进入 mesos 的 localhost：5050查看该job 执行的 shell，结果如下  并没有我想象中的$cd log_dir， 请问marathon的相对路径是如何实现的呢？

<div class="post-text" itemprop="text"> <p>I've been unable to find an answer to this after days of Googling. I have a service running in Marathon/Mesos. I have a Prometheus cluster scraping metrics. My Marathon metrics port config looks like this:</p> <pre><code>{ "containerPort": 8081, "hostPort": 0, "servicePort": 31301, "protocol": "tcp", "labels": { "metrics": "/metrics" } } </code></pre> <p>Prometheus, configured with just a boilerplate marathon-sd config, successfully finds this target, but it then listens for metrics on: <code>__address__ = [NodeIP]:31301</code>; so it's listening on the host's IP with the service port, rather than the dynamically assigned host port, while the service port only matters for Marathon-LB. </p> <p>I know that Marathon defines the environment variable <code>$PORT0</code> in the container to be the host port, however I can't figure out how to access this from the Prometheus SD config, nor how to access other fields dynamically configured by Marathon like <code>Endpoints</code>. Does anyone have any suggestions? I can't/don't want to assign a static <code>hostPort</code> because I have more containers than there are physical nodes in the cluster, as is sort of the point with container orchestration. </p> </div>

在ubuntu下载marathon,部署codis,通过json文件启动dashboard服务，然后启动codis-fe,在页面创建group等操作时，都会提示“invalid xauth”错误，用f12查看时，显示，status code 800，这是什么原因，请指教

如题，mesos上运行marathon，如何配置marathon的role,尝试过在/etc/marathon/ conf/下写mesos_role文件，但是没有成功

<div class="post-text" itemprop="text"> <p>In Go, how can I parse the following JSON? I know to use <code>struct</code> to parse, but the keys are different for each entry, also they are not fixed, they can be more or less. </p> <pre><code>{ "consul": [], "docker": [], "etcd": ["etcd"], "kubernetes": ["secure"], "mantl-api": [], "marathon": ["marathon"], "mesos": ["agent", "follower", "leader", "master"], "mesos-consul": [], "zookeeper": ["mantl"] } </code></pre> <p>Thanks for help! </p> </div>

Problem Description 　　Changsha is a beautiful city surrounded by mountains and rivers, forming a charming scenery. There are many tourist attractions in Changsha: Yuelu Academy, the predecessor of Hunan University, which is one of the four most famous academies in China. It was established in 976A.D. in Northern Song Dynasty. Juzizhou Island (Orange Isle) is the world's longest inland river isle which lies in Xiangjiang River and it is famous for the famous poet Qinyuanchun-Changsha written by Chairman Mao. Mawangdui is a famous archaeological site that contains the tombs of three people from the Western Han Dynasty. The tomb of Xin Zhui is best preserved among the three with a complete cosmetic set, lacquered pieces and finely woven silk garments. Huogongdian represents the Huxiang culture and Chuwu culture, Hunan’s geography culture and Hunan’s distinctive food culture. Tourists can have a taste of typical Hunan cuisine in it. 　　Every year the city holds a marathon. When planning the route, the organizers wish to go pass some tourist attractions to make it more enjoyable to attract more athletes and audience. Changsha can be treated as a graph consisted of N intersections and many bidirectional roads. A road connects two intersections i and j with length Wi,j. However, to reduce the impact to the daily traffic, only N-1 roads specified by the local government which can connect all N intersections are allowed to be used as the route. And the intersections with only one adjacent intersection are on the west bank of Xiangjiang River and there are ferries only at these intersections. The marathon starts at the intersection called Red East Square (marked as S) in Hunan University by convention. The organizers do not want the route pass any road twice, so the marathon has to be separated into two sections, the first section and the second section. Two different points have to be selected from intersections on the bank to act as the half end point S1 and the half starting point S2. The first section starts from S and end in S1. The second section starts from S2 and end in S. The organizer will use ferryboats to transport athletes from S1 to S2 as required by the government. 　　Considering the safety, some supply points are to be set on some intersections on each half section and there must be a supply point set on S, S1 and S2. According to scientific research, the most suitable distance between two adjacent supply points is L and the organizers want to minimize the evaluation of the route. For each section, the evaluation from the starting point to rest point i is marked as Ei, and where j is the previous supply point on the route,　　means the sum of the roads’ length on the route from intersection j to i. The evaluation of the starting point is zero. The evaluation of a section equals to the evaluation from its starting point to end point. 　　Your task is to select S1, S2, and the supply points to minimize the total evaluation of both sections. Input 　　There are multiple test cases. 　　For each test case the first line contains two integers, N, L. (1<=N<=20000, 1<=L<=109) 　　The next N-1 lines with 3 integers, U, V, W, describes that a bidirectional road connects intersection U and V with distance W. (1<=U, V<=N, 1<=W<=103) Red East Square (S) is always numbered 1. The input will finish with the end of file. Output 　　For each case the output contains only one line, the evaluation of the best plan rounded to the second digit after the decimal point. If there is no solution, output -1. Sample Input 7 4 1 2 2 1 3 7 1 4 3 2 5 6 2 6 5 3 7 8 Sample Output 7.00

Problem Description 　　Changsha is a beautiful city surrounded by mountains and rivers, forming a charming scenery. There are many tourist attractions in Changsha: Yuelu Academy, the predecessor of Hunan University, which is one of the four most famous academies in China. It was established in 976A.D. in Northern Song Dynasty. Juzizhou Island (Orange Isle) is the world's longest inland river isle which lies in Xiangjiang River and it is famous for the famous poet Qinyuanchun-Changsha written by Chairman Mao. Mawangdui is a famous archaeological site that contains the tombs of three people from the Western Han Dynasty. The tomb of Xin Zhui is best preserved among the three with a complete cosmetic set, lacquered pieces and finely woven silk garments. Huogongdian represents the Huxiang culture and Chuwu culture, Hunan’s geography culture and Hunan’s distinctive food culture. Tourists can have a taste of typical Hunan cuisine in it. 　　Every year the city holds a marathon. When planning the route, the organizers wish to go pass some tourist attractions to make it more enjoyable to attract more athletes and audience. Changsha can be treated as a graph consisted of N intersections and many bidirectional roads. A road connects two intersections i and j with length Wi,j. However, to reduce the impact to the daily traffic, only N-1 roads specified by the local government which can connect all N intersections are allowed to be used as the route. And the intersections with only one adjacent intersection are on the west bank of Xiangjiang River and there are ferries only at these intersections. The marathon starts at the intersection called Red East Square (marked as S) in Hunan University by convention. The organizers do not want the route pass any road twice, so the marathon has to be separated into two sections, the first section and the second section. Two different points have to be selected from intersections on the bank to act as the half end point S1 and the half starting point S2. The first section starts from S and end in S1. The second section starts from S2 and end in S. The organizer will use ferryboats to transport athletes from S1 to S2 as required by the government. 　　Considering the safety, some supply points are to be set on some intersections on each half section and there must be a supply point set on S, S1 and S2. According to scientific research, the most suitable distance between two adjacent supply points is L and the organizers want to minimize the evaluation of the route. For each section, the evaluation from the starting point to rest point i is marked as Ei, and where j is the previous supply point on the route,　　means the sum of the roads’ length on the route from intersection j to i. The evaluation of the starting point is zero. The evaluation of a section equals to the evaluation from its starting point to end point. 　　Your task is to select S1, S2, and the supply points to minimize the total evaluation of both sections. Input 　　There are multiple test cases. 　　For each test case the first line contains two integers, N, L. (1<=N<=20000, 1<=L<=109) 　　The next N-1 lines with 3 integers, U, V, W, describes that a bidirectional road connects intersection U and V with distance W. (1<=U, V<=N, 1<=W<=103) Red East Square (S) is always numbered 1. The input will finish with the end of file. Output 　　For each case the output contains only one line, the evaluation of the best plan rounded to the second digit after the decimal point. If there is no solution, output -1. Sample Input 7 4 1 2 2 1 3 7 1 4 3 2 5 6 2 6 5 3 7 8 Sample Output 7.00

<div class="post-text" itemprop="text"> <p>I'm trying to start traefik with the boltdb backend. Sadly I always get a panic. Following my setup and the terminal output.</p> <h3>Start Command</h3> <pre><code>./traefik_darwin-amd64 -d -c config.toml </code></pre> <h3>config.toml</h3> <pre><code>debug = true defaultEntryPoints = ["http"] [entryPoints] [entryPoints.http] address = ":8081" [web] address = ":8082" [boltdb] endpoint = "/Users/tochti/Tmp/traefik.db" watch = true prefix = "/traefik" </code></pre> <h3>Terminal Output</h3> <p>After a long time of waiting the following panic is displayed</p> <p><a href="https://pastebin.com/1vUXbgTU" rel="nofollow noreferrer">https://pastebin.com/1vUXbgTU</a></p> <h3>Output of <code>traefik version</code>: (<em>What version of Traefik are you using?</em>)</h3> <pre><code>Version: v1.3.1 Codename: raclette Go version: go1.8.3 Built: 2017-06-16_11:00:34AM OS/Arch: darwin/amd64 </code></pre> <h3>What is your environment &amp; configuration (arguments, toml, provider, platform, ...)?</h3> <pre><code>{ "GraceTimeOut": 10000000000, "Debug": true, "CheckNewVersion": true, "AccessLogsFile": "", "TraefikLogsFile": "", "LogLevel": "ERROR", "EntryPoints": { "http": { "Network": "", "Address": ":8081", "TLS": null, "Redirect": null, "Auth": null, "Compress": false } }, "Cluster": null, "Constraints": [], "ACME": null, "DefaultEntryPoints": [ "http" ], "ProvidersThrottleDuration": 2000000000, "MaxIdleConnsPerHost": 200, "IdleTimeout": 180000000000, "InsecureSkipVerify": false, "Retry": null, "HealthCheck": { "Interval": 30000000000 }, "Docker": null, "File": null, "Web": { "Address": ":8082", "CertFile": "", "KeyFile": "", "ReadOnly": false, "Statistics": null, "Metrics": null, "Path": "", "Auth": null }, "Marathon": null, "Consul": null, "ConsulCatalog": null, "Etcd": null, "Zookeeper": null, "Boltdb": { "Watch": true, "Filename": "", "Constraints": [], "Endpoint": "/Users/tochti/Tmp/traefik.db", "Prefix": "/traefik", "TLS": null, "Username": "", "Password": "" }, "Kubernetes": null, "Mesos": null, "Eureka": null, "ECS": null, "Rancher": null, "DynamoDB": null, "ConfigFile": "/Users/tochti/Tmp/traefik_test/config.toml" } </code></pre> <h3>Bolt "traefik" Bucket Items</h3> <pre><code>/traefik/backends/srv1_example_com/servers/server_1/url http://127.0.0.1:32001 /traefik/frontends/srv1_example_com/backend srv1_example_com /traefik/frontends/srv1_example_com/routes/test_1/rule Host:srv1.example.com </code></pre> <p>Thanks for help!</p> </div>

MESOS master报错： ``` master.cpp:9445] Sending offers [ ce2fd812-b02c-473a-977f-c868e23b6367-O38, ce2fd812-b02c-473a-977f-c868e23b6367-O39 ] to framework cc289df0-a5be-43dd-98e5-798411f81915-0000 (marathon) at scheduler-0e550772-c11c-4dab-aa70-d51d62b534b0@172.17.0.3:46822 master.cpp:5837] Processing DECLINE call for offers: [ ce2fd812-b02c-473a-977f-c868e23b6367-O38 ] for framework cc289df0-a5be-43dd-98e5-798411f81915-0000 (marathon) at scheduler-0e550772-c11c-4dab-aa70-d51d62b534b0@172.17.0.3:46822 master.cpp:11439] Removing offer ce2fd812-b02c-473a-977f-c868e23b6367-O38 master.cpp:5837] Processing DECLINE call for offers: [ ce2fd812-b02c-473a-977f-c868e23b6367-O39 ] for framework cc289df0-a5be-43dd-98e5-798411f81915-0000 (marathon) at scheduler-0e550772-c11c-4dab-aa70-d51d62b534b0@172.17.0.3:46822 master.cpp:11439] Removing offer ce2fd812-b02c-473a-977f-c868e23b6367-O39 ``` Marathon报错： ``` [2018-12-29 08:49:28,394] INFO Processing offer: offerId ce2fd812-b02c-473a-977f-c868e23b6367-O38, agentId ce2fd812-b02c-473a-977f-c868e23b6367-S0 (mesosphere.marathon.core.launcher.impl.OfferProcessorImpl:Thread-172) [2018-12-29 08:49:28,395] INFO Processing offer: offerId ce2fd812-b02c-473a-977f-c868e23b6367-O39, agentId ce2fd812-b02c-473a-977f-c868e23b6367-S1 (mesosphere.marathon.core.launcher.impl.OfferProcessorImpl:Thread-172) [2018-12-29 08:49:28,395] INFO No match for:ce2fd812-b02c-473a-977f-c868e23b6367-O38 from:173.0.20.106 reason:No offers wanted (mesosphere.marathon.core.matcher.manager.impl.OfferMatcherManagerActor:marathon-akka.actor.default-dispatcher-20) [2018-12-29 08:49:28,395] INFO No match for:ce2fd812-b02c-473a-977f-c868e23b6367-O39 from:173.0.20.105 reason:No offers wanted (mesosphere.marathon.core.matcher.manager.impl.OfferMatcherManagerActor:marathon-akka.actor.default-dispatcher-20) ```

我是使用docker+marathon+mesos+zookeeper的框架 ，由于公司需求将marathon修改为了https访问方式，但是会出现marathon与mesos 交互时出现错误，所以需要将mesos也修改为https访问方式，我在mesos官网上看见有对ssl的支持，就是添加三个环境变量，但我按它的办法做了后并没有生效，请问有懂这方面的道友知道如何解决吗？

<div class="post-text" itemprop="text"> <p>We deploy services as docker containers using Marathon. The containers include a base config file, Marathon pulls an environment config file (which has a subset of the base keys) at deployment time so when the app starts it has;</p> <ul> <li>environment.toml</li> <li>config.toml</li> </ul> <p>when reading the config we need to conflate the values in both files to a single set, effectively masking/shadowing the values present in both files with those in the environment file.</p> <p>I didn't find this functionality in the Viper docs. Unless I have missed something it seems my options are;</p> <ul> <li>Write a package that uses Viper to read both files and perform the conflation.</li> <li>Extend Viper</li> </ul> <p>Before I start writing code, is there already a mechanism for doing this?</p> </div>

Problem Description Since members of Wuhan University ACM Team are lack of exercise, they plan to participate in a ten-thousand-people Marathon. It is common that the athletes run very fast at first but slow down later on. Start from this moment, we can assume that everyone is moving forward in a constant speed. ACMers love algorithms, so they want to know not only the result but also who may be in the leading position. Now we know all athletes' position and speed at a specific moment. The problem is, starting from this moment, how many athletes may be the leader. Please notice that there's no leader if two or more athletes are at the leading position at the same time. No two athletes may have the same speed. Input The input consists of several test cases. The first line of input consists of an integer T, indicating the number of test cases. The first line of each test case consists of an integer N, indicating the number of athletes. Each of the following N lines consists of two integers: p, v, indicating an athlete's position and speed. Technical Specification 1. T ≤ 20 2. 0 < N ≤ 50000 3. 0 < p, v ≤ 2000,000,000 4. An athlete's position is the distant between him/her and the start line. 5. The Marathon is so long that you can assume there's no finishline. Output For each test case, output the number of possible leaders on a separate line. Sample Input 1 3 1 1 2 3 3 2 Sample Output 2

Problem Description This year, Bruce Force spends his vacation in Flagstaff, Arizona, where he wants to practice for his next half marathon (a race over 21 km). At his first training he runs to his friend Greedy Gonzales' home which is 21 miles away from Flagstaff. Arriving there, he is very tired and realizes that 21 miles are much more than 21 km. Greedy Gonzales tells him that 21 km equals 13 miles. 21, 13? Bruce realizes immediately that there must be a deeper relation! Both, 13 and 21 are Fibonacci numbers! Fibonacci numbers can be defined as follows: F1 = 1 F2 = 2 Fn+1 = Fn+Fn-1 for n>1. Bruce has just learned about the Fibonacci number system at his university. Each positive integer x can be written as the sum of different Fibonacci numbers, so this means that there exists numbers k and b1, b2, ..., bk such that x = ∑i=1..k bi * Fi, where bk = 1 and bi (1 ≤ i < k) is either 0 or 1. In short, we can write the representation as: b(x) = (bk, bk-1, ..., b1). To make the representation unique, we require that bi * bi-1 = 0 for all i > 1. For example 21 can be represented as (1,0,0,0,0,0,0) and 13 as (1,0,0,0,0,0) in the Fibonacci system. Bruce notices that one can convert a distance x in kilometers into a corresponding distance y to miles as follows: First, write down x in its Fibonacci system representation b(x). Second, shift the bits of b(x) one position to the right (the last bit is deleted) and get b(y). Third, calculate y from b(y) by evaluating the sum given above. For example, the number 42 written in the Fibonacci system is (1,0,0,1,0,0,0,0). In step two we would shift the bits one position to the right and get (1,0,0,1,0,0,0). In the third step, we would calculate 0*1 + 0*2 + 0*3 + 1*5 + 0*8 + 0*13 + 1*21 = 26. Now it's your turn to write a program for Bruce that converts kilometers into miles according to Bruce's algorithm. Input The first line of the input contains t, the number of distances Bruce wants to convert from kilometers to miles (0<t<25000). Each of the next t lines contains an integer distance x (2 < x < 25000) in kilometers. Output For each distance x in kilometers output the distance y in miles calculated according to Bruce's algorithm. Sample Input 5 42 100 180 300 360 Sample Output 26 62 111 185 222

Problem Description 　　Changsha is a beautiful city surrounded by mountains and rivers, forming a charming scenery. There are many tourist attractions in Changsha: Yuelu Academy, the predecessor of Hunan University, which is one of the four most famous academies in China. It was established in 976A.D. in Northern Song Dynasty. Juzizhou Island (Orange Isle) is the world's longest inland river isle which lies in Xiangjiang River and it is famous for the famous poet Qinyuanchun-Changsha written by Chairman Mao. Mawangdui is a famous archaeological site that contains the tombs of three people from the Western Han Dynasty. The tomb of Xin Zhui is best preserved among the three with a complete cosmetic set, lacquered pieces and finely woven silk garments. Huogongdian represents the Huxiang culture and Chuwu culture, Hunan’s geography culture and Hunan’s distinctive food culture. Tourists can have a taste of typical Hunan cuisine in it. 　　Every year the city holds a marathon. When planning the route, the organizers wish to go pass some tourist attractions to make it more enjoyable to attract more athletes and audience. Changsha can be treated as a graph consisted of N intersections and many bidirectional roads. A road connects two intersections i and j with length Wi,j. However, to reduce the impact to the daily traffic, only N-1 roads specified by the local government which can connect all N intersections are allowed to be used as the route. And the intersections with only one adjacent intersection are on the west bank of Xiangjiang River and there are ferries only at these intersections. The marathon starts at the intersection called Red East Square (marked as S) in Hunan University by convention. The organizers do not want the route pass any road twice, so the marathon has to be separated into two sections, the first section and the second section. Two different points have to be selected from intersections on the bank to act as the half end point S1 and the half starting point S2. The first section starts from S and end in S1. The second section starts from S2 and end in S. The organizer will use ferryboats to transport athletes from S1 to S2 as required by the government. 　　Considering the safety, some supply points are to be set on some intersections on each half section and there must be a supply point set on S, S1 and S2. According to scientific research, the most suitable distance between two adjacent supply points is L and the organizers want to minimize the evaluation of the route. For each section, the evaluation from the starting point to rest point i is marked as Ei, and where j is the previous supply point on the route,　　means the sum of the roads’ length on the route from intersection j to i. The evaluation of the starting point is zero. The evaluation of a section equals to the evaluation from its starting point to end point. 　　Your task is to select S1, S2, and the supply points to minimize the total evaluation of both sections. Input 　　There are multiple test cases. 　　For each test case the first line contains two integers, N, L. (1<=N<=20000, 1<=L<=109) 　　The next N-1 lines with 3 integers, U, V, W, describes that a bidirectional road connects intersection U and V with distance W. (1<=U, V<=N, 1<=W<=103) Red East Square (S) is always numbered 1. The input will finish with the end of file. Output 　　For each case the output contains only one line, the evaluation of the best plan rounded to the second digit after the decimal point. If there is no solution, output -1. Sample Input 7 4 1 2 2 1 3 7 1 4 3 2 5 6 2 6 5 3 7 8 Sample Output 7.00

<div class="post-text" itemprop="text"> <p>I'm trying to get a value from <a href="https://github.com/gambol99/go-marathon/blob/master/events.go#L107" rel="nofollow noreferrer">an interface</a> (it should be a pointer to another struct, <a href="https://github.com/gambol99/go-marathon/blob/master/events.go#L356" rel="nofollow noreferrer">see</a>). Actually, I have to know the type of the pointer to access to the data it and it bother me. That's why I would like to use <a href="https://golang.org/pkg/reflect/" rel="nofollow noreferrer">reflect package</a> to do it better.</p> <p>Actually, I can display the type using <code>reflect.TypeOf(event.Event).String()</code> but I don't understand how to change <a href="https://github.com/gambol99/go-marathon/blob/master/examples/events_sse_transport/main.go#L73" rel="nofollow noreferrer">this line</a> in the example without specifying with something like <code>.(*marathon.EventDeploymentStepSuccess)</code></p> </div>

大学四年，看课本是不可能一直看课本的了，对于学习，特别是自学，善于搜索网上的一些资源来辅助，还是非常有必要的，下面我就把这几年私藏的各种资源，网站贡献出来给你们。主要有：电子书搜索、实用工具、在线视频学习网站、非视频学习网站、软件下载、面试/求职必备网站。 注意：文中提到的所有资源，文末我都给你整理好了，你们只管拿去，如果觉得不错，转发、分享就是最大的支持了。 一、电子书搜索 对于大部分程序员...

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程序员在一个周末的时间，得了重病，差点当场去世，还好及时挽救回来了。

昨天早上通过远程的方式 review 了两名新来同事的代码，大部分代码都写得很漂亮，严谨的同时注释也很到位，这令我非常满意。但当我看到他们当中有一个人写的 switch 语句时，还是忍不住破口大骂：“我擦，小王，你丫写的 switch 语句也太老土了吧！” 来看看小王写的代码吧，看完不要骂我装逼啊。 private static String createPlayer(PlayerTypes p...

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loonggg读完需要3分钟速读仅需 1 分钟大家好，我是你们的校长。我之前讲过，这年头，只要肯动脑，肯行动，程序员凭借自己的技术，赚钱的方式还是有很多种的。仅仅靠在公司出卖自己的劳动时...

最近有个老铁，告诉我说，上班一个月，后悔当初着急入职现在公司了。他之前在美图做手机研发，今年美图那边今年也有一波组织优化调整，他是其中一个，在协商离职后，当时捉急找工作上班，因为有房贷供着，不能没有收入来源。所以匆忙选了一家公司，实际上是一个大型外包公司，主要派遣给其他手机厂商做外包项目。**当时承诺待遇还不错，所以就立马入职去上班了。但是后面入职后，发现薪酬待遇这块并不是HR所说那样，那个HR自...

昨天看到一档综艺节目，讨论了两个话题：（1）中国学生的数学成绩，平均下来看，会比国外好？为什么？（2）男生的数学成绩，平均下来看，会比女生好？为什么？同时，我又联想到了一个技术圈经常讨...

提到“程序员”，多数人脑海里首先想到的大约是：为人木讷、薪水超高、工作枯燥…… 然而，当离开工作岗位，撕去层层标签，脱下“程序员”这身外套，有的人生动又有趣，马上展现出了完全不同的A/B面人生！ 不论是简单的爱好，还是正经的副业，他们都干得同样出色。偶尔，还能和程序员的特质结合，产生奇妙的“化学反应”。 @Charlotte：平日素颜示人，周末美妆博主 大家都以为程序媛也个个不修边幅，但我们也许...

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不说了，字节跳动也反手把我挂了。

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二哥，有个事想询问下您的意见，您觉得应届生值得去外包吗？公司虽然挺大的，中xx，但待遇感觉挺低，马上要报到，挺纠结的。

当HR压你价，说你只值7K时，你可以流畅地回答，记住，是流畅，不能犹豫。 礼貌地说：“7K是吗？了解了。嗯~其实我对贵司的面试官印象很好。只不过，现在我的手头上已经有一份11K的offer。来面试，主要也是自己对贵司挺有兴趣的，所以过来看看……”（未完） 这段话主要是陪HR互诈的同时，从公司兴趣，公司职员印象上，都给予对方正面的肯定，既能提升HR的好感度，又能让谈判气氛融洽，为后面的发挥留足空间。...

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面试阿里p7被问到的问题(当时我只知道第一个)：@Conditional是做什么的?@Conditional多个条件是什么逻辑关系？条件判断在什么时候执...

我们程序员应该抱着尝鲜、猎奇的心态，否则就容易固步自封，技术停滞不前。

编程语言层出不穷，从最初的机器语言到如今2500种以上的高级语言，程序员们大呼“学到头秃”。程序员一边面临编程语言不断推陈出新，一边面临由于许多代码已存在，程序员编写新应用程序时存在重复“搬砖”的现象。 无代码/低代码编程应运而生。无代码/低代码是一种创建应用的方法，它可以让开发者使用最少的编码知识来快速开发应用程序。开发者通过图形界面中，可视化建模来组装和配置应用程序。这样一来，开发者直...

最近面试了一个31岁8年经验的程序猿，让我有点感慨，大龄程序猿该何去何从。

说实话，自己的算法，我一个不会，太难了吧

已经连续五年参加大厂校招、社招的技术面试工作，简历看的不下于万份 这篇文章会用实例告诉你，什么是差的程序员简历！ 疫情快要结束了，各个公司也都开始春招了，作为即将红遍大江南北的新晋UP主，那当然要为小伙伴们做点事（手动狗头）。 就在公众号里公开征简历，义务帮大家看，并一一点评。《启舰：春招在即，义务帮大家看看简历吧》 一石激起千层浪，三天收到两百多封简历。 花光了两个星期的所有空闲时...

我们都玩过Windows操作系统中的经典游戏扫雷（Minesweeper），如果把质数当作一颗雷，那么，表格中红色的数字哪些是雷（质数）？您能找出多少个呢？文中用列表的方式罗列了10000以内的自然数、质数（素数），6的倍数等，方便大家观察质数的分布规律及特性，以便对算法求解有指导意义。另外，判断质数是初学算法，理解算法重要性的一个非常好的案例。

正确选择比瞎努力更重要！

两个星期以前，就有读者强烈要求我写一篇 Java Stream 流的文章，我说市面上不是已经有很多了吗，结果你猜他怎么说：“就想看你写的啊！”你看你看，多么苍白的喜欢啊。那就“勉为其难”写一篇吧，嘻嘻。 单从“Stream”这个单词上来看，它似乎和 java.io 包下的 InputStream 和 OutputStream 有些关系。实际上呢，没毛关系。Java 8 新增的 Stream 是为...

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