Man Page adjacent_find.3

                       Standard C++ Library
             Copyright 1998, Rogue Wave Software, Inc.

NAME

     adjacent_find

      - Find the first adjacent pair of elements  in  a  sequence
     that are equivalent.

SYNOPSIS

     #include <algorithm>
     template <class ForwardIterator>
      ForwardIterator
      adjacent_find(ForwardIterator first,
                    ForwardIterator last);

     template <class ForwardIterator, class BinaryPredicate>
     ForwardIterator
      adjacent_find(ForwardIterator first, ForwardIterator last,
                    BinaryPredicate pred);

DESCRIPTION

     There are two versions of the adjacent_find  algorithm.  The
     first  finds equal adjacent elements in the sequence defined
     by iterators first and last and returns an iterator i point-
     ing  to  the first of the equal elements. The second version
     lets you specify your own binary function to test for a con-
     dition.  It  returns  an iterator i pointing to the first of
     the pair of elements that meet the conditions of the  binary
     function.  In  other  words, adjacent_find returns the first
     iterator i such that both i and i  +  1  are  in  the  range
     [first,  last)  for  which  one  of the following conditions
     holds:

     *i == *(i + 1)

     or

     pred(*i,*(i + 1)) == true

     If adjacent_find does not find a match, it returns last.

COMPLEXITY

     adjacent_find  performs  exactly  find(first,last,value)   -
     first applications of the corresponding predicate.

EXAMPLE

     //
     // find.cpp
     //
     #include <vector>
     #include <algorithm>
     #include <iostream>
     using namespace std;

     int main()
      {
       typedef vector<int>::iterator iterator;
       int d1[10] = {0,1,2,2,3,4,2,2,6,7};

        // Set up a vector
       vector<int> v1(d1,d1 + 10);

        // Try find
       iterator it1 = find(v1.begin(),v1.end(),3);

        // Try find_if
       iterator it2 =
        find_if(v1.begin(),v1.end(),bind1st(equal_to<int>(),3));

        // Try both adjacent_find variants
       iterator it3 = adjacent_find(v1.begin(),v1.end());

       iterator it4 =
          adjacent_find(v1.begin(),v1.end(),equal_to<int>());

        // Output results
       cout << *it1 << " " << *it2 << " " << *it3 << " "
             << *it4 << endl;

       return 0;
      }

     Program Output :




     3 3 2 2

WARNINGS

     If your compiler does not support default  template  parame-
     ters,  then you always need to supply the Allocator template
     argument. For instance, you have to write:

     vector<int,allocator<int> >

     instead of:

     vector<int>

     If your compiler does not support namespaces,  then  you  do
     not need the using declaration for std.

SEE ALSO

     find