The unordered_multiset::swap() is a built-in function in C++ STL which swaps the contents of two unordered_multiset
containers.
Note: Both of the containers should have the same type of elements. Sizes of the containers may differ.
Syntax:
unordered_multiset1.swap(unordered_multiset2);
Parameters: The function accepts only one compulsory parameter i.e unordered_multiset2 with which the swapping of unordered_multiset1 is to be done.
Return Value: It does not return any value.
Below programs illustrate the above function.
Program 1:
C++
// C++ program to illustrate // unordered_multiset::swap() #include <iostream> #include <string> #include <unordered_set> using namespace std;
// Function to display the contents of multiset s. void display(unordered_multiset< int > s)
{ for ( auto it = s.begin(); it != s.end(); it++)
cout << *it<< " " ;
cout<< "\n" ;
} int main()
{ // Declaration
unordered_multiset< int > s1, s2;
// initializing both multisets(sizes are different)
s1 = { 1, 2, 3, 4 };
s2 = { 10, 20, 30, 40, 50 };
// displaying initial values
cout << "Initial values of s1 are: \n" ;
display(s1);
cout << endl;
cout << "Initial values of s2 are: \n" ;
display(s2);
cout << endl;
// swapping the values
s1.swap(s2);
// display final values
cout << "Final values of s1 are: \n" ;
display(s1);
cout << endl;
cout << "Final values of s2 are: \n" ;
display(s2);
return 0;
} |
Output:
Initial values of s1 are: 4 3 2 1 Initial values of s2 are: 50 40 30 20 10 Final values of s1 are: 50 40 30 20 10 Final values of s2 are: 4 3 2 1
Program 2:
C++
// C++ program to illustrate // unordered_multiset::swap() #include <iostream> #include <string> #include <unordered_set> using namespace std;
// Function to display the contents of multiset s void display(unordered_multiset<string> s)
{ for ( auto it = s.begin(); it != s.end(); it++)
cout << *it << " " ;
cout<<endl;
} int main()
{ // Declaration
unordered_multiset<string> s1, s2;
// Initializing both multisets(sizes are different)
s1 = { "Geeks" , "for" , "Geeks" };
s2 = { "Computer" , "Science" , "Portal" , "for" , "Geeks" };
// Displaying initial values
cout << "Initial values of s1 are: \n" ;
display(s1);
cout << endl;
cout << "Initial values of s2 are: \n" ;
display(s2);
cout << endl;
// Swapping
s1.swap(s2);
// Display final values
cout << "Final values of s1 are: \n" ;
display(s1);
cout << endl;
cout << "Final values of s2 are: \n" ;
display(s2);
return 0;
} |
Output:
Initial values of s1 are: for Geeks Geeks Initial values of s2 are: Geeks for Portal Science Computer Final values of s1 are: Geeks for Portal Science Computer Final values of s2 are: for Geeks Geeks