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How can mixed data types (int, float, char, etc) be stored in an array?

...minated union, aka tagged union. struct { enum { is_int, is_float, is_char } type; union { int ival; float fval; char cval; } val; } my_array[10]; The type member is used to hold the choice of which member of the union is should be used for each array element. ...
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Are there disadvantages to using a generic varchar(255) for all text-based fields?

...e , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothe...
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Take a char input from the Scanner

I am trying to find a way to take a char input from the keyboard. 22 Answers 22 ...
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Is there a way to specify how many characters of a string to print out using printf()?

Is there a way to specify how many characters of a string to print out (similar to decimal places in int s)? 8 Answers ...
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Datatype for storing ip address in SQL Server

...VARCHAR(15)) RETURNS BINARY(4) AS BEGIN DECLARE @bin AS BINARY(4) SELECT @bin = CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1)) + CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1)) + CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1)) ...
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Conveniently Declaring Compile-Time Strings in C++

...y cumbersome, as the string needs to be declared as a variadic sequence of characters, e.g. 15 Answers ...
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convert a char* to std::string

...g to store data retrieved by fgets() . To do this I need to convert the char* return value from fgets() into an std::string to store in an array. How can this be done? ...
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uint8_t can't be printed with cout

... It doesn't really print a blank, but most probably the ASCII character with value 5, which is non-printable (or invisible). There's a number of invisible ASCII character codes, most of them below value 32, which is the blank actually. You have to convert aa to unsigned int to output t...
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getting type T from IEnumerable

... t.GetGenericTypeDefinition() == typeof(IEnumerable<>)) .Select(t => t.GetGenericArguments()[0]); } Some objects implement more than one generic IEnumerable so it is necessary to return an enumeration of them. Edit: Although, I have to say, it's a terrible idea for a class to...
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How can I use mySQL replace() to replace strings in multiple records?

...GREATERTHAN', '>'), 'LESSTHAN', '<') You can also do this when you select the data (as opposed to when you save it). So instead of : SELECT MyURLString From MyTable You could do SELECT REPLACE (MyURLString, 'GREATERTHAN', '>') as MyURLString From MyTable ...