Interview script of Software Test Engineer

test questions 1． Enter a web address in the browser address bar , What happens next ？

answer ： The actions that occur are as follows .

（1） The browser finds the URL IP Address .

（2） The browser parses the results IP Address to Web Server sends a HTTP request .

（3） The server receives the request and processes it .

（4） The server returns a response .

（5） The browser decodes the response , And render the display page .

（6） After the page is displayed , Browser sends asynchronous request .

test questions 2． explain Java The difference between memory leak and overflow in .

answer ： out of memory （out of memory） When a program requests memory , There is not enough memory space available .

Memory leak （memory leak） Refers to the program after applying for memory , Unable to free requested memory space . The harm of a memory leak can be ignored , But the consequences of memory leak accumulation are very serious , No matter how much memory the computer has , Sooner or later, it will be used up .

A memory leak will eventually lead to a memory overflow .

test questions 3． Write a Java Single instance mode of .

test questions 4． Suppose there are two volumes 5L and 6L The barrel , Finally, how to only install 3L water ？

answer ： The specific method is as follows .

（1） take 6L water , Pour in 5L In the barrel , Or get 6L What's left in the bucket 1L water .

（2） hold 5L The barrel is empty , Take the 1L Water in 5L Keep it in the bucket , take 6L water , Pour in 5L In the barrel ,6L What the bucket gets is 2L water , hold 5L The barrel is empty , Store this 2L water .

（3）5L In the bucket 2L water , Retake 6L water , Pour in 5L In the barrel , The water poured in is 6L?3L=3L,5L The bucket is full ,6L What's left in the bucket is just 3L water .

test questions 5． Pointed out that Web Testing and App The difference in testing .

answer ： In terms of compatibility ,Web Consider browsers ,App In addition to considering different mobile phone models , Also need to consider App Version of .

On the Internet ,App Consider using 3G、4G still Wi-Fi Network, etc .

Meituan interview questions and answers

test questions 1． Explain the difference between abstract classes and interfaces .

answer ： Abstract classes are used to capture the general characteristics of subclasses . It cannot instantiate , Superclasses that can only be used as subclasses . Abstract classes are used to create templates for subclasses in the inheritance level .

An interface is a collection of abstract methods . If a class implements an interface , It inherits the abstract method of this interface . It's like a contract model , If you implement this interface , You must make sure to use these methods . Interface is just a form , The interface itself can't do anything .

test questions 2． If the tester says the program has bug, And the developers just say no , What to do with ？

answer ： Speak with data , Check with the demand analyst .

test questions 3．Android What are the four components of the system ？

answer ： The four components are Activity、Service、BroadCastReceiver、ContentProvider, They are Android Foundation of the system .

test questions 4．Java How to implement exception handling of ？

answer ：Java The exception handling of is through try、catch、finally、throw、throws Keyword to implement .

test questions 5． How polymorphism is embodied ？

answer ： polymorphic , It means overloading and rewriting . Overload occurs in a class ; Overrides occur in subclasses , That is, the subclass overrides the method with the same name as the parent class .

test questions 6． Design a test plan , Including test progress and required personnel .

answer ： The test plan is as follows .

（1） Testers participate in requirements review in the early stage .

（2） test 、 Developers participate in system analysis and review .

（3） Testers design use cases , And with the development of 、 Product personnel review together .

（4） After development and testing , Perform the test 、 feedback 、 verification .

（5） Test and do pre delivery acceptance together with product personnel .

（6） Release .

Real questions and answers of the annual beauty group interview

test questions 1． Yes 10 A bottle , In each bottle 1000 Tablet medicine , Each tablet in each bottle may weigh 1g, It may also be heavy 0.9g, But I'm not sure that each tablet in several bottles is 0.9g Of . There is an electronic scale , Accuracy of 0.1g, Ask how to determine which bottle each tablet is 0.9g Of ？

analysis ： Decompose the topic , Because I'm not sure how many bottles it is , It's a little bit more complicated , Let's start with a simple place , Divide the problem into warm-up questions and advanced questions .

（1） Warm up questions ： Yes 10 A bottle , Each bottle has 1000 Tablet medicine , Each tablet in each bottle may weigh 1g, It may also be heavy 0.9g, Each tablet in a bottle weighs 0.9g Of . There is a steelyard , Accuracy of 0.1g, Weigh once how to determine which bottle each tablet is 0.9g Of ？

（2） Advanced questions ： Yes 10 A bottle , Each bottle has 1000 Tablet medicine , Each tablet in each bottle may weigh 1g, It may also be heavy 0.9g, Each tablet in the two bottles weighs 0.9g Of . There is a steelyard , Accuracy of 0.1g, How to weigh each tablet in which two bottles 0.9g？

answer ： For questions （1）, If there is only one bottle, each tablet is 0.9g, How to solve this problem ？ Because you can only weigh it once , So the idea is how to display the serial number of the marked bottle through the results obtained in a weighing . If you can only weigh it once , How to do ？

In fact, we know the weight difference between the two tablets 0.1g, From 1 Take it from a bottle 1 slice , From 2 Take it from a bottle 2 slice , The first 1 A tablet in a bottle is better than 1g Less 0.1g, So the first 1 Each tablet in a bottle weighs 0.9g. If the first 2 The ratio of two tablets in a bottle 2g Less 0.2g, So the first 2 Each tablet in a bottle weighs 0.9g, So the question （1） It's easy to solve , Take... Separately 1 slice 、2 slice ,……,10 Just take a slice .

For questions （2）, The key point is to combine the previous problems in pairs , Make the next number of tablets different from the possible combination of the first two bottles .

problem （2）, Take... Separately 1 slice 、2 slice 、4 slice 、7 slice 、10 slice 、13 slice 、16 slice ……

For the final question , Readers should have ideas , That is, it needs to be different from all the previous combinations .

therefore , Take... Separately 1 slice 、2 slice 、4 slice 、8 slice 、16 slice 、32 slice ……

These pieces are just 2 Of n Power , For the first 10 bottle , take 29 slice , namely 512 slice , This is why the question is 1000 slice ,10 bottle .

test questions 2． Here are two glass balls , There is a building 100 A high-rise building , What are the conditions for the glass ball to break ？

answer ： Every time, you must try from the lower floor to the higher floor , Until on the floor f(k), The first ball has broken , Record the floor of the last attempt as f(k?1), On this floor , The glass ball won't break , So next try f(k?1)+1, f(k?1)+2, f(k?3)+3,…… Until one floor broke , The worst thing is to arrive f(k) ?1 layer .

The next solution is easy to come up with . Since in the first step （ Determine the critical section ） The number of throwing glass balls is increasing , Let's take the second step （ Determine the critical layer ） The number of floors decreases as the number of first steps increases . The number of throws in the first step is increased one at a time , Then reduce the number of throws in the second step one at a time .

Suppose the number of layers thrown for the first time is f, Turn it into a mathematical model ,f+(f?1)+…+2+1 It means the from f Start guessing , Each increment is less than the previous increment ?1? Under the circumstances , The last guess （ namely f+(f?1)+…+2+1）, According to the meaning of the question f+(f?1)+…+ 2+1≥99, namely f?(f+1)/2≥99（ First test point selection 100 Layers are meaningless , It's bound to break , And there is no test value , So the first test point k yes 1～99 A number of ）, Find out f?>13.5. The number of floors where the first glass ball is dropped is 14、27、39、50、60、69、77、84、90、95、99.

Why is the front f+(f?1)+…+2+1≥99？ First , In order to determine the critical segment by segment , We need to ensure that no matter which critical section the glass ball breaks , The number of judgments is the same , Therefore, the length of each segment from bottom to top is less than that of the previous segment 1, At the same time, the total length of all segments is 99（ It doesn't have to be 100, Because if the front is not broken , that 100 There is no need to judge ）.

Why is the right side of the inequality 99 Well ？ Actually , Regardless of use 99 still 100, The final result is the same , It's just 99 Easier to understand , Because if you have arrived 99 The layer , But the glass ball still didn't break , So the answer must be 100 了 , therefore 100 Don't guess . If you say something during the interview 99 and 100 The relationship between , That means you are smart , As for the use 100 still 99, Different people have different understandings .

For the first time , If you choose 14 floor , Then the highest one can judge ？ According to the sequence ｛14,27,39,50,60,69,77,84,90,95,99,102,104,105｝, Guess 14 Time , And finally 105 layer . According to the above 99 and 100 The relationship between , Although I guessed 14 Time , But I guessed it for the last time 105 layer , It can be seen that if 105 The glass ball is not broken , Then it must be in the 106 The glass ball broke .14 The second largest can be judged to the 106 layer , therefore 15 Time is from 15 Start guessing , And if there is 107 layer , You need to 15 Time .

If in the first place 27 The glass ball is broken , From 15 Start trying layer by layer , And if in the 26 The glass ball is broken , Then guess the sequence is ｛14,27,15,16,17,18,19,20,21,22,23,24,25,26｝, I guess 14 Time .

Why can't we use dichotomy ？ Whether the dichotomy is the most 7 It can be done once ？ This question requires that you can only use two glass balls at most to judge the critical floor when the glass ball breaks . If we use dichotomy , The first step is 50 The layer broke up as soon as it was thrown , Then you can only start from 1 The layer began to throw away , To carry out 50 Second judgment （ If you go on in the 25 Layer throw , The last glass ball broke , You have no ball to use ）, So it is not suitable to use dichotomy here . therefore , We can only use the first glass ball to determine a range as above , Then judge from the bottom of the interval up in the interval .

test questions 3．HTTP What kinds of requests are there ？ What's the use of each ？

answer ： There are the following 8 Kind of .

OPTIONS： Returns the server's support for a specific resource HTML Request method , or Web Test server functions sent by the server （ Allow clients to view server performance ）.

GET： Make a request to a specific resource （ Request specific page information , And return the entity body ）.

POST： Submit data to the specified resource to process the request （ Submit Form 、 Upload files ）, It may lead to the establishment of new resources or the modification of existing resources .

PUT： Upload the latest content to the specified resource location （ Replace the contents of the specified file with the data transmitted from the client to the server ）.

HEAD： And GET The request is similar to , There is no specific content in the response returned , For getting headers .

DELETE： Request server delete request-URL Identified resources （ Ask the server to delete the page ）.

TRACE： Echo requests received by server , For testing and diagnosis .

CONNECT：HTTP/1.1 The connection can be changed into pipe Proxy server of mode