operator!= (unordered_set)

Tests whether the unordered_set object on the left side of the operator is not equal to the unordered_set object on the right side.

bool operator!=( 
   const unordered_set <Key, Hash, Pred, Allocator>& _Left, 
   const unordered_set <Key, Hash, Pred, Allocator>& _Right 
);

Parameters

  • _Left
    An object of type unordered_set.

  • _Right
    An object of type unordered_set.

Return Value

true if the unordered_sets are not equal; false if they are equal.

Remarks

The comparison between unordered_set objects is not affected by the arbitrary order in which they store their elements. Two unordered_sets are equal if they have the same number of elements and the elements in one container are a permutation of the elements in the other container. Otherwise, they are unequal.

Example

// unordered_set_ne.cpp 
// compile by using: cl.exe /EHsc /nologo /W4 /MTd 
#include <unordered_set> 
#include <iostream> 
#include <ios>

int main() 
{ 
    using namespace std;

    unordered_set<char> c1, c2, c3;

    c1.insert('a'); 
    c1.insert('b'); 
    c1.insert('c'); 

    c2.insert('c'); 
    c2.insert('a'); 
    c2.insert('d'); 

    c3.insert('c'); 
    c3.insert('a'); 
    c3.insert('b'); 

   cout << boolalpha;
   cout << "c1 != c2: " << (c1 != c2) << endl; 
   cout << "c1 != c3: " << (c1 != c3) << endl; 
   cout << "c2 != c3: " << (c2 != c3) << endl; 

    return (0); 
} 

Output:

c1 != c2: true

c1 != c3: false

c2 != c3: true

Requirements

Header: <unordered_set>

Namespace: std

See Also

Reference

Standard Template Library