How to use the set::find STL function in Visual C++

Note Microsoft Visual C++ .NET 2002 and Microsoft Visual C++ .NET 2003 support both the managed code model that is provided by the Microsoft .NET Framework and the unmanaged native Microsoft Windows code model. The information in this article applies only to unmanaged Visual C++ code. Microsoft Visual C++ 2005 supports both the managed code model that is provided by the Microsoft .NET Framework and the unmanaged native Microsoft Windows code model.

Summary

The following sample code illustrates how to use the set::find STL function in Visual C++.

More Information

Required Header

   <set>

Prototype

   template<class _K, class _Pr, class _A>
class set {
public:
// Function 1:

const_iterator find(const _K& _Kv) const;

}


NOTE: The class/parameter names in the prototype may not match the version in the header file. Some have been modified to improve readability.

Description

The find function is used to locate an element in a controlled sequence. It returns an iterator to the first element in the controlled sequence whose sort key matches its parameter. If no such element exists, the returned iterator equals end().

Sample Code

NOTE: The first line in the sample code section says:
// Compile options needed: /GX
In Visual C++ .NET and in Visual C++ 2005, /EHsc is set by default and is equivalent to /GX.
////////////////////////////////////////////////////////////////////// 
//
// Compile options needed: -GX
//
// SetFind.cpp:
// Illustrates how to use the find function to get an iterator
// that points to the first element in the controlled sequence
// that has a particular sort key.
//
// Functions:
//
// find Returns an iterator that points to the first element
// in the controlled sequence that has the same sort key
// as the value passed to the find function. If no such
// element exists, the iterator equals end().
//
// Written by Derek Jamison
// of Microsoft Technical Support,
// Copyright (c) 1996 Microsoft Corporation. All rights reserved.
//////////////////////////////////////////////////////////////////////

#pragma warning(disable:4786)

#include <set>
#include <iostream>

#if _MSC_VER > 1020 // if VC++ version is > 4.2
using namespace std; // std c++ libs implemented in std
#endif

typedef set<int,less<int>,allocator<int> > SET_INT;

void truefalse(int x)

{
cout << (x?"True":"False") << endl;
}

void main() {

SET_INT s1;
cout << "s1.insert(5)" << endl;
s1.insert(5);
cout << "s1.insert(8)" << endl;
s1.insert(8);
cout << "s1.insert(12)" << endl;
s1.insert(12);

SET_INT::iterator it;
cout << "it=find(8)" << endl;
it=s1.find(8);
cout << "it!=s1.end() returned ";
truefalse(it!=s1.end()); // True

cout << "it=find(6)" << endl;
it=s1.find(6);
cout << "it!=s1.end() returned ";
truefalse(it!=s1.end()); // False
}

Program Output

s1.insert(5)
s1.insert(8)
s1.insert(12)
it=find(8)
it!=s1.end() returned True
it=find(6)
it!=s1.end() returned False

References

Visual C++ Books Online: Visual C++ Books; C/C++; Standard C++ Library Reference
Propiedades

Id. de artículo: 158576 - Última revisión: 06/22/2014 - Revisión: 1

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