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querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
... would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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How does this print “hello world”?
...th this codification scheme you can have all 26 (one case) english letters and 6 symbols (being space among them).
Algorithm description
The >>= 5 in the for-loop jumps from group to group, then the 5-bits group gets isolated ANDing the number with the mask 31₁₀ = 11111₂ in the sentenc...
Capture Image from Camera and Display in Activity
I want to write a module where on a click of a button the camera opens and I can click and capture an image. If I don't like the image I can delete it and click one more image and then select the image and it should return back and display that image in the activity.
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How to upgrade Git to latest version on macOS?
I just bought a new Mac with OS X Lion and I checked in the Terminal what version of git is installed by default. I got the answer
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How to remove all the occurrences of a char in c++ string
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Basically, replace replaces a character with another and '' is not a character. What you're looking for is erase.
See this question which answers the same problem. In your case:
#include <algorithm>
str.erase(std::remove(str.begin(), str.end(), 'a'), str.end());
Or us...
Pipe output and capture exit status in Bash
I want to execute a long running command in Bash, and both capture its exit status, and tee its output.
15 Answers
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Choosing between std::map and std::unordered_map [duplicate]
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It is very important to understand that for some applications, worst case performance is crucial to know and is the deciding factor. For some hard real-time systems, having a linear worst case like the hashtable is not acceptable. std::map is always O(lg N...
How to send email attachments?
I am having problems understanding how to email an attachment using Python. I have successfully emailed simple messages with the smtplib . Could someone please explain how to send an attachment in an email. I know there are other posts online but as a Python beginner I find them hard to understand....
Get a list of URLs from a site [closed]
...pecified: 159.121.ssss Please make sure to specify the correct website URL and resubmit your request.
– JustJohn
Jul 26 '16 at 21:29
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Is there a way to measure how sorted a list is?
...Formally, let A(1), A(2), ..., A(n) be a sequence of n numbers.If i < j and A(i) > A(j), then the pair (i,j) is called an inversion of A.
The inversion number of a sequence is one common measure of its sortedness.Formally, the inversion number is defined to be the number of inversions, that is...