logo
down
shadow

C++ using std::set remove duplicate item for a struct fail.


C++ using std::set remove duplicate item for a struct fail.

Content Index :

C++ using std::set remove duplicate item for a struct fail.
Tag : cpp , By : ezzze
Date : November 24 2020, 05:44 AM

wish help you to fix your issue std::set detects duplicates by means of the trichotomy law, which states that if !cmp(a, b) && !cmp(b, a) then eq(a, b), for some order relation cmp and some equivalence relation eq. If you want eq to stand for equal, you need to provide a order relation cmp that models a strict total ordering between TokenTerms. One such ordering is the lexicographical order, which can be readily achieved by way of std::tie. Here's a complete example:
#include <set>
#include <tuple>
#include <string>
#include <iostream>

typedef unsigned int uint32_t;

struct TokenTerm {
    std::string     value;
    std::string     type;
    uint32_t        start_pos;
    uint32_t        end_pos;
};

struct TokenTermCmp {
    bool operator()(TokenTerm const& x, TokenTerm const& y) const {
        return std::tie(x.value, x.type, x.start_pos, x.end_pos) < std::tie(y.value, y.type, y.start_pos, y.end_pos);
    }
};

int main() {
    std::set<TokenTerm, TokenTermCmp> tokens;
    tokens.insert({"value", "type", 0, 10});
    tokens.insert({"value", "type", 0, 10});

    for (auto&& token: tokens) 
        std::cout << token.value << ", "
                  << token.type << ", "
                  << token.start_pos << ", "         
                  << token.end_pos
                  << '\n';
}

Comments
No Comments Right Now !

Boards Message :
You Must Login Or Sign Up to Add Your Comments .

Share : facebook icon twitter icon

Linq to XML: Remove duplicate from an item


Tag : chash , By : jay
Date : March 29 2020, 07:55 AM
To fix the issue you can do I have an xml file containing things like these:
var contents = XDocument.Parse(xml);

// Select only elements that have the language attribute
var result = from item in contents.Descendants()
             where item.Attribute("language") != null
             select item;

// Returns only those elements that have at least another element
// with the same value.
var resultDuplicates = result
    .GroupBy(s => s.Value)
    .SelectMany(grp => grp.Skip(1));

// If duplicates found, replace them in the original xml.
if (resultDuplicates.Count() > 0)
{
    foreach(var entry in resultDuplicates)
        xml = xml.Replace(entry.ToString(), string.Empty);
}

BOOLEAN allocate_items(struct item * items, size_t howmany) function for allocate an array of struct item


Tag : c , By : DotNetWise
Date : March 29 2020, 07:55 AM
around this issue First of all, both line 4 and 6, as you mentioned seems to be OK.
That said, the basic problem with this function is, you're allocating memory to a local scope of variable. This way

Remove Item from Struct (Swift)


Tag : ios , By : ERaubenheimer
Date : March 29 2020, 07:55 AM
I hope this helps you . Find the index of object and remove it, which matches your song title and artist
let index = favoriteSongs.index{ $0.title == songs[thisSong].title && $0.artist == songs[thisSong].artist}
if let index = index {
    favoriteSongs.remove(at: index)
}

How to remove duplicate item in Dart


Tag : dart , By : DonMac
Date : March 29 2020, 07:55 AM
To fix this issue So here is how i set my data
tempNotification.toSet().toList() 
class Notification {
  final String notificationId;
  ...
  bool operator ==(o) => o is Notification && notificationId == o.notificationId;
  int get hashCode => notificationId.hashCode;
}

Remove duplicate structs in array based on struct property in Swift


Tag : ios , By : Eric
Date : March 29 2020, 07:55 AM
Related Posts Related QUESTIONS :
  • How to handle classes with differently named member functions in algorithms?
  • Convert QString to QJsonArray
  • Data exchange finished in CPropertyPage::OnOK?
  • Template member specialization in template class
  • Is it not possible to assign a struct to an index of a vector?
  • Why is empty unordered_map.find not returning end()?
  • Template argument deduction for inheriting specializations
  • dlopen undefined reference
  • Member function of class with template arguments and default arguments outside class
  • Is it possible to implement a non-owning "slightly smart" pointer on top of standard weak pointers?
  • how to configure the AcquireCredentialsHandleA correctly
  • Using private versions of global extern variables with OpenMP
  • Eigen Block wrong amount of columns and rows
  • Memory alignment rules in inheritance
  • Is nullptr falsy?
  • tm_wday returns a large integer outside 0-6 range
  • Scope a using declaration, inside a header
  • How to specify constructor's template arguments inside a new expression?
  • Sort an array via x86 Assembly (embedded in C++)?? Possible?
  • How to Replace only Part of the Variable using #define
  • How do you compare the performace of valarrays vs built-in arrays?
  • Is it normal for C++ static initialization to appear twice in the same backtrace?
  • c++ generate a good random seed for psudo random number generators
  • Why isn't my operator overloading working properly?
  • Getting meaningful error messages from fstream's in C++
  • C++: Converting Julian dates to Gregorian
  • Could someone explain this interesting behaviour with Sleep(1)?
  • Is it possible to roll a significantly faster version of modf
  • Updating pointer using signals and slots
  • How are classes more secure than structures?
  • finding "distance" between two pixel's colors
  • C++ Greatest Number Verification
  • Why does my token return NULL and how can I fix it?(c++)
  • C++ enforce conditions on inherited classes
  • what happened if an exception is not captured?
  • Redundant naming in C/C++ typedefs/structs
  • question about STL thread-safe and STL debugging
  • killing a separate thread having a socket
  • Returning the size of available virtual memory at run-time in C++
  • Parallel computing for integrals
  • How do I force my std::map to deallocate memory used?
  • C++ Templates: implicit conversion, no matching function for call to ctor
  • Adding python script to c++ project
  • C++ private pointer "leaking"?
  • Initializing Primitive Array to One Value
  • how is push_back implemented in STL vector?
  • C++ Profiling: KiFastSystemCallRet
  • Multiple rows with a single INSERT in SQLServer 2008
  • Use super class's address/pointer in initialization list
  • double fork using vfork
  • Convert char pointer (char*) to struct
  • Does anyone have good tips for using pc-lint?
  • C++ How fast is passing around objects?
  • template type's ctor arguments at instantiation time
  • Get list of windows in taskbar on Windows 7?
  • Curl connection options
  • Best cross-platform solution for network server?
  • simple c++ file opening issue
  • Switching from C++ (with a lot of STL use) to C for interpreter building
  • How can I access the JPEG image pixels as a 3D array like we do in MATLAB?
  • shadow
    Privacy Policy - Terms - Contact Us © scrbit.com