C++ Stack Library - operator= Function

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Description

The C++ function std::stack::operator= assigns new contents to the stack by replacing old ones. This method modifies size of the stack if necessary.

Declaration

Following is the declaration for std::stack::operator= function form std::stack header.

C++11

stack<T, Container>& 
operator=( stack<T,Container>&& other );

Parameters

x − Another stack object of same type.

Return value

Returns this pointer.

Exceptions

This member function never throws exception.

Time complexity

Linear i.e. O(n)

Example

The following example shows the usage of std::stack::operator= function.

#include <iostream>
#include <stack>

using namespace std;

int main(void) {
   stack<int> s1;
   stack<int> s2;

   for (int i = 0; i < 5; ++i)
      s1.push(i + 1);

   cout << "Size of stack s1 before move operation = " << s1.size() << endl;

   s2 = move(s1);

   cout << "Size of stack s1 after move operation = " << s1.size() << endl;

   cout << "Contents of stack s2" << endl;
   while (!s2.empty()) {
      cout << s2.top() << endl;
      s2.pop();
   }

   return 0;
}

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

Size of stack s1 before move operation = 5
Size of stack s1 after move operation = 0
Contents of stack s2
5
4
3
2
1