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What's the difference between backtracking and depth first search?

...tree.. Take any example that uses backtracking, like permuting a string of characters, there is no logical tree (no implicit tree) whatsoever regarding to the problem but we do have a recursion tree that models the incremental string building process. As for pruning, that's the pruning done to the r...
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How do I import .sql files into SQLite 3?

...d - you need ; on the end of your statements: create table server(name varchar(50),ipaddress varchar(15),id init); create table client(name varchar(50),ipaddress varchar(15),id init); share | impr...
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(How) can I count the items in an enum?

...hich does what I described. namespace gx { enum struct DnaNucleobase : char { A, C, G, T }; } Then: namespace std { template<> struct numeric_limits<enum ::gx::DnaNucleobase> { typedef enum ::gx::DnaNucleobase value_ty...
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#1071 - Specified key was too long; max key length is 767 bytes

...o 3072 bytes. You also have to be aware that if you set an index on a big char or varchar field which is utf8mb4 encoded, you have to divide the max index prefix length of 767 bytes (or 3072 bytes) by 4 resulting in 191. This is because the maximum length of a utf8mb4 character is four bytes. For a...
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What is boxing and unboxing and what are the trade offs?

...ect o = i;// Boxing int j = (int)o;// UnBoxing Value Types are: int, char and structures, enumerations. Reference Types are: Classes,interfaces,arrays,strings and objects share | improve this ...
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Is there a way to check if int is legal enum in C#?

...nt, absolutely nothing else Enum names in C# must begin with an alphabetic character No valid enum name can being with a minus sign: - Calling ToString() on an enum returns either the int value if no enum (flag or not) is matched. If an allowed enum value is matched, it will print the name of the ...
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How to convert std::string to LPCWSTR in C++ (Unicode)

... int len; int slength = (int)s.length() + 1; len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0); wchar_t* buf = new wchar_t[len]; MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len); std::wstring r(buf); delete[] buf; return r; } std::wstring stemp...
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What is base 64 encoding used for?

...You never know -- some protocols may interpret your binary data as control characters (like a modem), or your binary data could be screwed up because the underlying protocol might think that you've entered a special character combination (like how FTP translates line endings). So to get around th...
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Why do most C developers use define instead of const? [duplicate]

...s is actually my preference in such a case. enum { FIELD_WIDTH = 16384 }; char buf[FIELD_WIDTH]; In C++ this is a huge advantage as you can scope your enum in a class or namespace, whereas you cannot scope a #define. In C you don't have namespaces and cannot scope an enum inside a struct, and am...
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Return a `struct` from a function in C

... Yes, I can put an array inside a struct, but I cannot e.g. write typedef char arr[100]; arr foo() { ... } An array cannot be returned, even if the size is known. – Giorgio Mar 11 '12 at 11:19 ...