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std::multiset::value_comp(3)  C++ Standard Libary std::multiset::value_comp(3)

NAME
       std::multiset::value_comp - std::multiset::value_comp

Synopsis
	  std::multiset::value_compare value_comp() const;

	  Returns the function object that compares the	values.	It is the same
       as key_comp.

Parameters
	  (none)

Return value
	  The value comparison function	object.

Complexity
	  Constant.

Example
       // Run this code

	#include <cassert>
	#include <iostream>
	#include <set>

	// Example module 97 key compare function
	struct ModCmp {
	    bool operator()(const int lhs, const int rhs) const
	    {
		return (lhs % 97) < (rhs % 97);
	    }
	};

	int main()
	{
	    std::multiset<int, ModCmp> cont{1, 2, 3, 4,	5};

	    // Same behaviour as key_comp()
	    auto comp_func = cont.value_comp();

	    const int val = 100;

	    for	(int key : cont) {
		bool before = comp_func(key, val);
		bool after = comp_func(val, key);
		if (!before && !after)
		    std::cout << key <<	" equivalent to	key " << val <<	'\n';
		else if	(before)
		    std::cout << key <<	" goes before key " << val << '\n';
		else if	(after)
		    std::cout << key <<	" goes after key " << val << '\n';
		else
		    assert(0); // Cannot happen
	    }
	}

Output:
	1 goes before key 100
	2 goes before key 100
	3 equivalent to	key 100
	4 goes after key 100
	5 goes after key 100

See also
	  key_comp returns the function	that compares keys
		   (public member function)

http://cppreference.com		  2022.07.31	  std::multiset::value_comp(3)

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