replace_if (STL Samples)
Illustrates how to use the replace_if Standard Template Library (STL) function in Visual C++.
template<class ForwardIterator, class Predicate, class Type> inline
void replace_if(
ForwardIterator First,
ForwardIterator Last,
Predicate Pred,
const Type& Value
)
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 replace_if algorithm replaces all elements from the range [First, Last) that cause the predicate to return true with Value.
Example
// replace_if.cpp
// compile with: /EHsc
// Illustrates how to use the replace_if function.
//
// Functions:
// replace_if - Replace all elements from the sequence that
// satisfies a predicate with a specified value.
// disable warning C4786: symbol greater than 255 characters,
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
using namespace std;
int main()
{
const int VECTOR_SIZE = 8 ;
// Define a template class vector of integers
typedef vector<int > IntVector ;
//Define an iterator for template class vector of integer
typedef IntVector::iterator IntVectorIt ;
IntVector Numbers(VECTOR_SIZE) ; //vector containing numbers
IntVectorIt start, end, it ;
start = Numbers.begin() ; // location of first
// element of Numbers
end = Numbers.end() ; // one past the location
// last element of Numbers
//Initialize vector Numbers
Numbers[0] = 10 ;
Numbers[1] = 20 ;
Numbers[2] = 10 ;
Numbers[3] = 15 ;
Numbers[4] = 12 ;
Numbers[5] = 7 ;
Numbers[6] = 9 ;
Numbers[7] = 10 ;
cout << "Before calling replace_if" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// replace all elements from Numbers that are <= 10 with 4
replace_if(start, end, bind2nd(less_equal<int>(), 10), 4 ) ;
cout << "After calling replace_if" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
}
Output
Before calling replace_if
Numbers { 10 20 10 15 12 7 9 10 }
After calling replace_if
Numbers { 4 20 4 15 12 4 4 4 }
Requirements
Header: <algorithm>