stack::size (STL Samples)

Illustrates how to use the stack::size Standard Template Library (STL) function in Visual C++.

template<class _TYPE, class _C, class _A>
   size_type stack::size( ) const;

Remarks

注意

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::size function returns the number of elements in the stack. It is okay to call this function with an empty stack; it will return a value of 0.

Example

// StackSize.cpp
// compile with: /EHsc
// Illustrates how to use the size function to determine
// the number of elements on the stack.
//
// Functions:
//
//    size :  returns the number of elements in the stack.
//////////////////////////////////////////////////////////////////////

#pragma warning(disable:4786)
#include <stack>
#include <string>
#include <iostream>

using namespace std ;

typedef stack<string> STACK_STRING;

int main()
{
   STACK_STRING stack1;

   // Check the size of an empty stack. Should return 0.
   cout << "stack1.size() equals " << stack1.size() << endl;

   // Add item "Hello" to Stack1.
   cout << "stack1.push('Hello')" << endl;
   stack1.push("Hello");

   // Add item "This is the second element" to Stack1.
   cout << "stack1.push('This is the second element')" << endl;
   stack1.push("This is the second element");

   // Check the size of Stack1. Should return 2.
   cout << "stack1.size() equals " << stack1.size() << endl << endl;

   // Add item "Third element" to Stack1.
   cout << "stack1.push('Third element')" << endl;
   stack1.push("Third element");

   // Check the size of Stack1. Should return 3.
   cout << "stack1.size() equals " << stack1.size() << endl << endl;

   // Pop "Third element".
   cout << "stack1.pop()" << endl;
   stack1.pop();

   // Pop "This is the second element".
   cout << "stack1.pop()" << endl;
   stack1.pop();

   // Check the size of Stack1 again. Should return 1.
   cout << "stack1.size() equals " << stack1.size()  << endl << endl;

   // Pop "Hello".
   cout << "stack1.pop()" << endl;
   stack1.pop();

   // Check the size of Stack1. Should return 0.
   cout << "stack1.size() equals " << stack1.size() << endl;
}

Output

stack1.size() equals 0
stack1.push('Hello')
stack1.push('This is the second element')
stack1.size() equals 2

stack1.push('Third element')
stack1.size() equals 3

stack1.pop()
stack1.pop()
stack1.size() equals 1

stack1.pop()
stack1.size() equals 0

Requirements

Header: <stack>

See Also

Concepts

Standard Template Library Samples