max_element

Algorithm

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Finds maximum value in a range.

None

#include <algorithm>

template <class ForwardIterator>
 ForwardIterator
 max_element(ForwardIterator first, ForwardIterator last);

template <class ForwardIterator, class Compare>
 ForwardIterator
 max_element(ForwardIterator first, ForwardIterator last,
             Compare comp);

The max_element algorithm returns an iterator that denotes the maximum element in a sequence. If the sequence contains more than one copy of the element, the iterator points to its first occurrence. The optional argument comp defines a comparison function that can be used in place of the default operator<. This function can be used with all the datatypes provided by the standard library.

Algorithm max_element returns the first iterator i in the range [first, last) such that for any iterator j in the same range the following corresponding conditions hold:

!(*i < *j) 

or

comp(*i, *j) == false. 

Exactly max((last - first) - 1, 0) applications of the corresponding comparisons are done for max_element.

//
// max_elem.cpp
//
 #include <algorithm>
 #include <vector>
 #include <iostream.h>
 
 int main(void)
 {
   typedef vector<int>::iterator iterator; 
   int d1[5] = {1,3,5,32,64};
  

   // set up vector 
   vector<int>      v1(d1,d1 + 5); 

   // find the largest element in the vector
   iterator it1 = max_element(v1.begin(), v1.end());
   // it1 = v1.begin() + 4
 
   // find the largest element in the range from
   // the beginning of the vector to the 2nd to last
   iterator it2 = max_element(v1.begin(), v1.end()-1, 
                      less<int>());   
   // it2 = v1.begin() + 3
 
   // find the smallest element 
   iterator it3 = min_element(v1.begin(), v1.end());  
   // it3 = v1.begin() 
 
   // find the smallest value in the range from
   // the beginning of the vector plus 1 to the end
   iterator it4 = min_element(v1.begin()+1, v1.end(), 
                      less<int>());      
   // it4 = v1.begin() + 1

   cout << *it1 << " " << *it2 << " " 
        << *it3 << " " << *it4 << endl;
 
   return 0;
 }

Output :
64 32 1 3

If your compiler does not support default template parameters then you need to always supply the Allocator template argument. For instance you'll have to write:

vector<int,allocator<int> >

instead of:

vector<int>

max, min, min_element

©Copyright 1996, Rogue Wave Software, Inc.