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System design - Payment - Amazon
Payment System - payment backend of e-commenrce appfunc: pay-in flow pay-out flownonfunc: reliability: handle failed payments reconciliationdeepDive: PSP integration reconciliation handle payment processing delays h...…
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System design - Uber
System Design - UberReferenceFunctional Requirements1.Users should be able to see all the cabs available with minimum price and ETA2.Users should be able to book a cab for their destination3.Users should be able to see the location of the driver4....…
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LC 75
Monotonic StackPB 739. Daily Temperaturestemperatures = [73,74,75,71,69,72,76,73]Output: [1,1,4,2,1,1,0,0]因为要找变暖的日子，也就是温度比现在大的，stack每次遇到新的element，stack里边所有比cur小的数都要pop出去，新元素就是他们要的日子class Solution { public int[] dailyTemperatures(int[] temperatu...…
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Minimum Operations to Make All Array Elements Equal
2602. Minimum Operations to Make All Array Elements EqualInput: nums = [3,1,6,8], queries = [1,5]Output: [14,10]Explanation: For the first query we can do the following operations:- Decrease nums[0] 2 times, so that nums = [1,1,6,8].- Decrease num...…
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Remove Duplicated elements
27. Remove ElementSolution: 快慢指针，慢指针左边是final result [0, slow),nums[slow - 1] is the last number should keep. 每次遇到符合的，更新nums[slow]就行class Solution { public int removeElement(int[] nums, int val) { int i = 0, j = 0; while (i < nu...…
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System design - Twitter
System design - Twittercommon features Post Tweet (support media file - image, vedio, etc.) User follow each other homefeed (timeline) search favorite (favorite posts) Retweet metrics & analytic ...…
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System design basic - cache write policy
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System design basic - media file uploading
Large Video/Image Upload (chunked/multipart uploads)Uploading large files in single request can lead to timeouts or failure due to network instability. Instead, breaking large files into smaller chunks and uploading them sequestially or in paralle...…
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System design - notification system
Notification system designdigestWhen talk about notification system, below features should be in your mind: Notification Types: Email SMS push notification (app not in use like lock sreen message) in-app notification (...…
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System design basic - HTTP Request vs HTTP Long-Polling vs WebSocket vs Server-Sent Events
HTTP Request vs HTTP Long-Polling vs WebSocket vs Server-Sent EventsIn this blog, we are going to learn the HTTP Request vs Http Long-Polling vs WebSocket vs Server-Sent Events(SSE).These are important when it comes to system design interviews.Fir...…
