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How do you append an int to a string in C++? [duplicate]
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Following on Eric's comment: char cstr[10];sprintf(cstr,"Player %d",i); or char *cstr;asprintf(cstr,"Player %d",i);
– tomsmeding
Dec 26 '13 at 17:33
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Reshaping data.frame from wide to long format
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Here is another example showing the use of gather from tidyr. You can select the columns to gather either by removing them individually (as I do here), or by including the years you want explicitly.
Note that, to handle the commas (and X's added if check.names = FALSE is not set), I am also us...
SQL Server loop - how do I loop through a set of records
how do I loop through a set of records from a select?
8 Answers
8
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How can I set the default value for an HTML element?
I thought that adding a "value" attribute set on the <select> element below would cause the <option> containing my provided "value" to be selected by default:
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How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
Javascript/jQuery: Set Values (Selection) in a multiple Select
I have a multiple select:
8 Answers
8
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Add a column to a table, if it does not already exist
...onstruct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
share
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How can I do an UPDATE statement with JOIN in SQL Server?
...oesn't support MERGE):
ANSI/ISO:
update ud
set assid = (
select sale.assid
from sale
where sale.udid = ud.id
)
where exists (
select *
from sale
where sale.udid = ud.id
);
MySQL:
update ud u
inner join sale s on
u.id = s.udid
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What is meant by immutable?
...omething like this:
// Assume string is stored like this:
struct String { char* characters; unsigned int length; };
// Passing pointers because Java is pass-by-reference
struct String* substring(struct String* in, unsigned int begin, unsigned int end)
{
struct String* out = malloc(sizeof(struc...
Position of least significant bit that is set
...x077CB531U)) >> 27];
}
}
return total;
}
unsigned char lowestBitTable[256];
int get_lowest_set_bit(unsigned num) {
unsigned mask = 1;
for (int cnt = 1; cnt <= 32; cnt++, mask <<= 1) {
if (num & mask) {
return cnt;
}
}
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