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What does {0} mean when initializing an object?
When {0} is used to initialize an object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
...
Divide a number by 3 without using *, /, +, -, % operators
... x = t;
}
return y;
}
int divideby3(int num)
{
int sum = 0;
while (num > 3) {
sum = add(num >> 2, sum);
num = add(num >> 2, num & 3);
}
if (num == 3)
sum = add(sum, 1);
return sum;
}
As Jim commented this works, because:...
Create an index on a huge MySQL production table without table locking
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[2017] Update: MySQL 5.6 has support for online index updates
https://dev.mysql.com/doc/refman/8.0/en/innodb-online-ddl-operations.html#online-ddl-index-syntax-notes
In MySQL 5.6 and higher, the table remains available for...
What is this operator in MySQL?
...e the regular = operator, two values are compared and the result is either 0 (not equal) or 1 (equal); in other words: 'a' <=> 'b' yields 0 and 'a' <=> 'a' yields 1.
Unlike the regular = operator, values of NULL don't have a special meaning and so it never yields NULL as a possible outco...
In Ruby how do I generate a long string of repeated text?
...
310
str = "0" * 999999
...
How do I get the different parts of a Flask request's url?
I want to detect if the request came from the localhost:5000 or foo.herokuapp.com host and what path was requested. How do I get this information about a Flask request?
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How do I convert a float number to a whole number in JavaScript?
... 5 5
~~value // 5 5 5
value | 0 // 5 5 5
value >> 0 // 5 5 5
value >>> 0 // 5 5 5
value - value % 1 // 5 5 5
Negative
// val...
Why does parseInt yield NaN with Array#map?
...ex of the element.
In this case, you ended up calling parseInt with radix 0, 1 and 2 in turn. The first is the same as not supplying the parameter, so it defaulted based on the input (base 10, in this case). Base 1 is an impossible number base, and 3 is not a valid number in base 2:
parseInt('1'...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
...
The full list of readyState values is:
State Description
0 The request is not initialized
1 The request has been set up
2 The request has been sent
3 The request is in process
4 The request is complete
(from https://www.w3schools.com/js/js_ajax_http_respo...
Cluster analysis in R: determine the optimal number of clusters
...
1024
If your question is how can I determine how many clusters are appropriate for a kmeans analysi...