C++ Programming Code Examples
C++ > Visual C++ 5.0 Standard C++ Library Code Examples
The count algorithm counts the number of elements in the range [first, last +1)
The count algorithm counts the number of elements in the range [first, last +1)
count
Header
<algorithm>
template<class InputIterator, class T> inline
size_t count(InputIterator first, InputIterator last, const T& value)
The count algorithm counts the number of elements in the range [first, last +1) that match value and returns the number of matching elements.
Sample
// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <algorithm>
#include <functional>
#include <string>
#include <vector>
using namespace std;
void main()
{
const int VECTOR_SIZE = 8 ;
// Define a template class vector of strings
typedef vector<string > StringVector ;
//Define an iterator for template class vector of strings
typedef StringVector::iterator StringVectorIt ;
StringVector NamesVect(VECTOR_SIZE) ; //vector containing names
string value("Sea") ; // stores the value used
// to count matching elements
StringVectorIt start, end, it ;
int result = 0 ; // stores count of elements
// that match value.
// Initialize vector NamesVect
NamesVect[0] = "She" ;
NamesVect[1] = "Sells" ;
NamesVect[2] = "Sea" ;
NamesVect[3] = "Shells" ;
NamesVect[4] = "by" ;
NamesVect[5] = "the" ;
NamesVect[6] = "Sea" ;
NamesVect[7] = "Shore" ;
start = NamesVect.begin() ; // location of first
// element of NamesVect
end = NamesVect.end() ; // one past the location
// last element of NamesVect
// print content of NamesVect
cout << "NamesVect { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// Count the number of elements in the range [first, last +1)
// that match value.
result = count(start, end, value) ;
// print the count of elements that match value
cout << "Number of elements that match \"Sea\" = "
<< result << endl ;
}
Program Output
NamesVect { She Sells Sea Shells by the Sea Shore }
Number of elements that match "Sea" = 2
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