给定a、b两个文件，各存放50亿个url，每个url各占用64字节，内存限制是4G，如何找出a、b文件共同的url？，50亿4g
给定a、b两个文件，各存放50亿个url，每个url各占用64字节，内存限制是4G，如何找出a、b文件共同的url？，50亿4g
可以估计每个文件的大小为5G*64=300G，远大于4G。所以不可能将其完全加载到内存中处理。考虑采取分而治之的方法。
遍历文件a，对每个url求取hash(url)%1000，然后根据所得值将url分别存储到1000个小文件（设为a0,a1,...a999）当中。这样每个小文件的大小约为300M。遍历文件b，采取和a相同的方法将url分别存储到1000个小文件(b0,b1....b999)中。这样处理后，所有可能相同的url都在对应的小文件(a0 vs b0, a1 vs b1....a999 vs b999)当中，不对应的小文件（比如a0 vs b99）不可能有相同的url。然后我们只要求出1000对小文件中相同的url即可。
比如对于a0 vs b0，我们可以遍历a0，将其中的url存储到hash_map当中。然后遍历b0，如果url在hash_map中，则说明此url在a和b中同时存在，保存到文件中即可。
如果分成的小文件不均匀，导致有些小文件太大（比如大于2G），可以考虑将这些太大的小文件再按类似的方法分成小小文件即可
昨天百度面试官问道的 今天研究一下
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1386
52
Large memory optimization, what should I do if the computer upgrades to 16g/32g memory speed and there is no change?
Jun 18, 2024 pm 06:51 PM
For mechanical hard drives or SATA solid-state drives, you will feel the increase in software running speed. If it is an NVME hard drive, you may not feel it. 1. Import the registry into the desktop and create a new text document, copy and paste the following content, save it as 1.reg, then right-click to merge and restart the computer. WindowsRegistryEditorVersion5.00[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SessionManager\MemoryManagement]"DisablePagingExecutive"=d
What to do if the 0x80004005 error code appears. The editor will teach you how to solve the 0x80004005 error code.
Mar 21, 2024 pm 09:17 PM
When deleting or decompressing a folder on your computer, sometimes a prompt dialog box "Error 0x80004005: Unspecified Error" will pop up. How should you solve this situation? There are actually many reasons why the error code 0x80004005 is prompted, but most of them are caused by viruses. We can re-register the dll to solve the problem. Below, the editor will explain to you the experience of handling the 0x80004005 error code. Some users are prompted with error code 0X80004005 when using their computers. The 0x80004005 error is mainly caused by the computer not correctly registering certain dynamic link library files, or by a firewall that does not allow HTTPS connections between the computer and the Internet. So how about
Sources say Samsung Electronics and SK Hynix will commercialize stacked mobile memory after 2026
Sep 03, 2024 pm 02:15 PM
According to news from this website on September 3, Korean media etnews reported yesterday (local time) that Samsung Electronics and SK Hynix’s “HBM-like” stacked structure mobile memory products will be commercialized after 2026. Sources said that the two Korean memory giants regard stacked mobile memory as an important source of future revenue and plan to expand "HBM-like memory" to smartphones, tablets and laptops to provide power for end-side AI. According to previous reports on this site, Samsung Electronics’ product is called LPWide I/O memory, and SK Hynix calls this technology VFO. The two companies have used roughly the same technical route, which is to combine fan-out packaging and vertical channels. Samsung Electronics’ LPWide I/O memory has a bit width of 512
Micron: HBM memory consumes 3 times the wafer volume, and production capacity is basically booked for next year
Mar 22, 2024 pm 08:16 PM
This site reported on March 21 that Micron held a conference call after releasing its quarterly financial report. At the conference, Micron CEO Sanjay Mehrotra said that compared to traditional memory, HBM consumes significantly more wafers. Micron said that when producing the same capacity at the same node, the current most advanced HBM3E memory consumes three times more wafers than standard DDR5, and it is expected that as performance improves and packaging complexity intensifies, in the future HBM4 This ratio will further increase. Referring to previous reports on this site, this high ratio is partly due to HBM’s low yield rate. HBM memory is stacked with multi-layer DRAM memory TSV connections. A problem with one layer means that the entire
Samsung announced the completion of 16-layer hybrid bonding stacking process technology verification, which is expected to be widely used in HBM4 memory
Apr 07, 2024 pm 09:19 PM
According to the report, Samsung Electronics executive Dae Woo Kim said that at the 2024 Korean Microelectronics and Packaging Society Annual Meeting, Samsung Electronics will complete the verification of the 16-layer hybrid bonding HBM memory technology. It is reported that this technology has passed technical verification. The report also stated that this technical verification will lay the foundation for the development of the memory market in the next few years. DaeWooKim said that Samsung Electronics has successfully manufactured a 16-layer stacked HBM3 memory based on hybrid bonding technology. The memory sample works normally. In the future, the 16-layer stacked hybrid bonding technology will be used for mass production of HBM4 memory. ▲Image source TheElec, same as below. Compared with the existing bonding process, hybrid bonding does not need to add bumps between DRAM memory layers, but directly connects the upper and lower layers copper to copper.
Lexar launches Ares Wings of War DDR5 7600 16GB x2 memory kit: Hynix A-die particles, 1,299 yuan
May 07, 2024 am 08:13 AM
According to news from this website on May 6, Lexar launched the Ares Wings of War series DDR57600CL36 overclocking memory. The 16GBx2 set will be available for pre-sale at 0:00 on May 7 with a deposit of 50 yuan, and the price is 1,299 yuan. Lexar Wings of War memory uses Hynix A-die memory chips, supports Intel XMP3.0, and provides the following two overclocking presets: 7600MT/s: CL36-46-46-961.4V8000MT/s: CL38-48-49 -1001.45V In terms of heat dissipation, this memory set is equipped with a 1.8mm thick all-aluminum heat dissipation vest and is equipped with PMIC's exclusive thermal conductive silicone grease pad. The memory uses 8 high-brightness LED beads and supports 13 RGB lighting modes.
How to remove comment restrictions on video accounts? What is the word limit for comments on a video account?
Mar 22, 2024 pm 02:11 PM
With the popularity of video accounts on social media, more and more people are beginning to use video accounts to share their daily lives, insights and stories. However, some users may experience comments being restricted, which can leave them confused and dissatisfied. 1. How to remove comment restrictions on video accounts? To lift the restriction on commenting on a video account, you must first ensure that the account has been properly registered and real-name authentication has been completed. Video accounts have requirements for comments. Only accounts that have completed real-name authentication can lift comment restrictions. If there are any abnormalities in the account, these issues need to be resolved before comment restrictions can be lifted. 2. Comply with the community standards of the video account. Video accounts have certain standards for comment content. If the comment involves illegal content, you will be restricted from speaking. To lift comment restrictions, you need to abide by the community of the video account
What should I do if the memory in win10 cannot be written?_How to solve the problem that the memory in win10 cannot be written
Mar 25, 2024 am 11:01 AM
Some users encountered a memory error prompt when using Win10, called "The memory cannot be written". What is going on? Below, the editor will share with you the solution to the Windows 10 system prompt "The memory cannot be written" 1. Press win+r to open the run function on the computer, enter services and msc, and then click OK. 2. Find the Windows Management Instrumentation service in the services window, click "Stop", and then click OK. 3. Still press win+r to open the computer’s run function and enter
