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What is a NullPointerException, and how do I fix it?
...c static void main(String[] args) {
Printer printer = new Printer("123");
printer.print();
}
}
See also:
Avoiding “!= null” statements in Java?
I still can't find the problem
If you tried to debug the problem and still don't have a solution, you can post a question for...
List comprehension vs map
...
10000 loops, best of 3: 181/118/123 usec per loop ^^^^^^^^^^^^^^^^^^
for list(<generator>), probably optimized
% python3 -mtimeit -s 'xs=range(1000)' 'f=lambda x:x' 'z=list(f(x) for x in xs)' ...
How to pass an array into a SQL Server stored procedure
...tion for this problem. You should only create an string expression like ';123;434;365;' in-which 123, 434 and 365 are some employeeIDs. By calling the below procedure and passing this expression to it, you can fetch your desired records. Easily you can join the "another table" into this query. This...
Why doesn't C# support the return of references?
...rn ref x;
else
return ref y;
}
and then call it with
int a = 123;
int b = 456;
ref int c = ref Max(ref a, ref b);
c += 100;
Console.WriteLine(b); // 556!
I know empirically that it is possible to build a version of C# that supports these features because I have done so. Advanced pr...
How do I (or can I) SELECT DISTINCT on multiple columns?
...would qualify as "distinct" (though looking identical to the human eye):
(123, NULL)
(123, NULL)
Also passes in a unique index and almost anywhere else, since NULL values do not compare equal according to the SQL standard. See:
Create unique constraint with null columns
OTOH, GROUP BY, DISTIN...
How can I transform between the two styles of public key format, one “BEGIN RSA PUBLIC KEY”, the oth
...01,083,183,234,323,797,142,810,155,862,553,705,570,600,021,649,944,369,726,123,996,534,870,137,000,784,980,673,984,909,570,977,377,882,585,701
Exponent: 65,537
The question then becomes how do we want to store these numbers in a computer. First we convert both to hexadecimal:
Modulus: EB506399F5...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
Is JavaScript an untyped language?
...licit compiler interjection, the instruction will error during run-time.
"12345" * 1 === 12345 // string * number => number
Strongly typed means there is a compiler, and it wants you an explicit cast from string to integer.
(int) "12345" * 1 === 12345
In either case, some compiler's featur...
Equation (expression) parser with precedence?
...p(1), pi: Math.atan2(1,1)*4 };
// input for parsing
// var r = { string: '123.45+33*8', offset: 0 };
// r is passed by reference: any change in r.offset is returned to the caller
// functions return the parsed/calculated value
function parseVal(r) {
var startOffset = r.offset;
var value;
...
PHP: How to remove all non printable characters in a string?
...ace is 14.79% faster
2048 chars str_replace 94.7111ms preg_replace 123.3189ms str_replace is 23.20% faster
4096 chars str_replace 227.7029ms preg_replace 258.3771ms str_replace is 11.87% faster
8192 chars str_replace 506.3410ms preg_replace 555.6269ms str_replace is 8.87% fas...