C++ List Library - merge() Function

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Description

The C++ function std::list::merge() merges two sorted lists into one. The lists should be sorted in ascending order.

Declaration

Following is the declaration for std::list::merge() function form std::list header.

C++98

 void merge (list& x); 

C++11

 void merge (list& x); 

Parameters

x − Another list object of same type.

Return value

None.

Exceptions

This member function never throws exception.

Time complexity

Linear i.e. O(n)

Example

The following example shows the usage of std::list::merge() function.

 #include <iostream> #include <list> using namespace std; int main(void) { list<int> l1 = {1, 5, 11, 31}; list<int> l2 = {10, 20, 30}; l2.merge(l1); cout << "List contains following elements after merge operation" << endl; for (auto it = l2.begin(); it != l2.end(); ++it) cout << *it << endl; return 0; } 

Let us compile and run the above program, this will produce the following result −

 List contains following elements after merge operation 1 5 10 11 20 30 31