java - Increment Decrement operator use -


this question has answer here:

in below programs , post increment operator used after completion of expression evaluation. first program shouldn't answer 40 n value of incremented 41.n likewise program 2 answer should 41 instead of 42?

class incrementdemo{ public static void main(string [] args){      int a=20;     a= a++ + a++;     system.out.println(a); //answer given 41 }  class incrementdemo{ public static void main(string [] args){      int a=20;     a= a++ + ++a;      system.out.println(a); }

answer given 42 second program.

you can understand behaviour if analyze how statement executed , state of a in meanwhile.

a = 20 a++ executed, 20 result of evaluation, = 21 second a++ executed, 21 result, = 22 2 results added, 20 + 21 = 41, = 41

on other side, in second case:

a = 20 a++ executed, 20 result of evaluation, = 21 ++a executed, = 22, 22 result 2 results added, 20 + 22 = 42, = 42

this because 2 increment operators evaluated sequentially, second sees effect of first one.


Comments

Post a Comment

Popular posts from this blog

php - Vagrant up error - Uncaught Reflection Exception: Class DOMDocument does not exist -

i've set bento/ubuntu-16.04 vagrant box using php 5.6, , getting following error quite few times when try , run shell script: "uncaught reflection exception: class domdocument not exist". i've tried adding following top of script (not together), each no success: "sudo apt-get install php5.6-xml", "sudo apt-get install php5-xml", "sudo apt-get install php-dom" i've tried resetting server "sudo service apache2 restart". does have suggestions?
Read more

vue.js - Create hooks for automated testing -

Image
qa guys complained can't automate frontend testing. because our html looks same outside. lazy hack did this <template> <div :role="$options.name"> ... </div> </template> <script> export default { name: 'vmcomponentname' } </script> which takes name script , applies html. in browser get: <div role="vmcomponentname"> ... </div> line :role="$options.name" goes in every component. is there dry er solutions? please share. additional details i'll explain in details looking for. imagine have vmusercreate form creates user. test case can create user . to automatically test without role, have use following selector: .wrapper > .wrapper > .wrapper > .submit-button the test extremely brittle (will break lot). if use roles can use [role="vmusercreateform"] .submit-button selector. many folds less brittle. so basically, i'm ...
Read more

Add new key value to json node in java -

i have json file : { "id":1, "name":"abc", "addressdetails": { "city":"newyork" } } i wanted add 1 more key-value ("pincode" : "414141") node 'addressdetails'. i tried using : objectmapper mapper = new objectmapper(); jsonnode root = mapper.readtree(new file("d://test.json")); objectnode node = mapper.createobjectnode(); node.with("addressdetails").put("pincode", "414141"); but it's not getting added, there way can ? you can try you should modify file path objectmapper mapper = new objectmapper(); objectnode nodes = mapper.readvalue(new file("d:\\test.txt"), objectnode.class); nodes.with("addressdetails").put("pincode", "414141"); mapper.writer().writevalue(new file("d:\\test.txt"), nodes);
Read more