C++ <stack> - operator== Function
The C++ <stack> operator== function is used to check whether two stacks are equal or not. It returns true if two stacks are equal, else returns false.
Syntax
template <class T, class Container> bool operator== (const stack<T,Container>& lhs, const stack<T,Container>& rhs);
template <class T, class Container> bool operator== (const stack<T,Container>& lhs, const stack<T,Container>& rhs);
Parameters
lhs |
First stack. |
rhs |
Second stack. |
Return Value
Returns true if the contents of lhs are equal to the contents of rhs, else returns false.
Time Complexity
Linear i.e, Θ(n).
Example:
In the example below, the operator== function is used to check whether two stacks are equal or not.
#include <iostream>
#include <stack>
using namespace std;
int main (){
stack<int> stk1;
stack<int> stk2;
for(int i = 0; i<3; i++) {
stk1.push(i);
stk2.push(i);
}
if (stk1 == stk2)
cout<<"stk1 and stk2 are equal.\n";
else
cout<<"stk1 and stk2 are not equal.\n";
stk1.pop();
cout<<"After deleting top element of stk1.\n";
if (stk1 == stk2)
cout<<"stk1 and stk2 are equal.\n";
else
cout<<"stk1 and stk2 are not equal.\n";
return 0;
}
The output of the above code will be:
stk1 and stk2 are equal. After deleting top element of stk1. stk1 and stk2 are not equal.
❮ C++ <stack> Library
