stack::operator==
Illustrates how to use the stack::operator== Standard Template Library (STL) function in Visual C++.
template<class _TYPE, class _C, class _A>
bool stack::bool operator==(
const stack<_TYPE, _C, _A>& _X
) const;
Remarks
Note
The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.
The stack::operator== function returns true if both stacks have equal elements arranged in the same sequence. The stack::operator== function always returns false if the two stacks are of a different size.
Example
// StackEqual.cpp
// compile with: /EHsc
// Illustrates how to use the stack::operator==
// function to determine if two stacks are equal.
//
// Functions:
// operator== : Returns true if both stacks are the same.
//////////////////////////////////////////////////////////////////////
#pragma warning(disable:4786)
#include <stack>
#include <iostream>
using namespace std ;
typedef stack<double> STACK_DOUBLE;
int main()
{
STACK_DOUBLE stack1,stack2;
// Add item 4.0 to Stack1.
cout << "stack1.push(4.0) s1=[4.0]" << endl;
stack1.push(4.0);
// Add item 3.0 to Stack1. Current Stack1 contains items 3.0 (top)
// 4.0 (bottom).
cout << "stack1.push(3.0) s1=[3.0 4.0]" << endl;
stack1.push(3.0);
// Add item 4.0 to Stack2.
cout << "stack2.push(4.0) s2=[4.0]" << endl;
stack2.push(4.0);
// Compare Stack1 and Stack2. Should return False.
cout << "stack1==stack2 is " <<
((stack1==stack2)? "True": "False") << endl << endl;
// Add item 6.0 to Stack2. Current Stack2 contains items 6.0 (top)
// 4.0 (bottom)
cout << "stack2.push(6.0) s2=[6.0 4.0]" << endl;
stack2.push(6.0);
// Compare Stack1 and Stack2. Should return False.
cout << "stack1==stack2 is " <<
((stack1==stack2)? "True": "False") << endl << endl;
// Keep adding item 8.0 to Stack2. Current Stack2 contains items
// 8.0 (top), 6.0 and 4.0 (bottom).
cout << "stack2.push(8.0) s2=[8.0 6.0 4.0]" << endl;
stack2.push(8.0);
// Compare Stack1 and Stack2. Should return False.
cout << "stack1==stack2 is " <<
((stack1==stack2)? "True": "False") << endl << endl;
// Delete the top item from Stack2. Current Stack2 contains items
// 6.0 (top) and 4.0 (bottom).
cout << "stack2.pop() s2=[6.0 4.0]" << endl;
stack2.pop();
// Delete another item from Stack2. Current Stack2 contains item 4.0.
cout << "stack2.pop() s2=[4.0]" << endl;
stack2.pop();
// Add item 3.0 to Stack2. Current Stack2 contains item 3.0 (top) and
// 4.0 (bottom).
cout << "stack2.push(3.0) s2=[3.0 4.0]" << endl;
stack2.push(3.0);
// Compare Stack2 and Stack2. Should return True.
cout << "stack1==stack2 is " <<
((stack1==stack2)? "True": "False") << endl << endl;
// Delete the top item from Stack2. Current Stack2 contains 4.0.
cout << "stack2.pop() s2=[4.0]" << endl;
stack2.pop();
// Delete another item from Stack2. Stack2 should be empty.
cout << "stack2.pop() s2=[]" << endl;
stack2.pop();
// Push item 8.0 to Stack2.
cout << "stack2.push(8.0) s2=[8.0]" << endl;
stack2.push(8.0);
// Compare Stack1 and Stack2. Should return False.
cout << "stack1==stack2 is " <<
((stack1==stack2)? "True": "False") << endl << endl;
}
Output
stack1.push(4.0) s1=[4.0]
stack1.push(3.0) s1=[3.0 4.0]
stack2.push(4.0) s2=[4.0]
stack1==stack2 is False
stack2.push(6.0) s2=[6.0 4.0]
stack1==stack2 is False
stack2.push(8.0) s2=[8.0 6.0 4.0]
stack1==stack2 is False
stack2.pop() s2=[6.0 4.0]
stack2.pop() s2=[4.0]
stack2.push(3.0) s2=[3.0 4.0]
stack1==stack2 is True
stack2.pop() s2=[4.0]
stack2.pop() s2=[]
stack2.push(8.0) s2=[8.0]
stack1==stack2 is False
Requirements
Header: <stack>