Source code
Declaration
template <class InputIterator, class T>
InputIterator find(InputIterator first, InputIterator last, const T& value);
template <class InputIterator, class Predicate>
InputIterator find_if(InputIterator first, InputIterator last,
Predicate pred);
Description The find function returns an iterator i referring to the first element in the range [ first, last) \ equal to value, or i = last if no element in the range is equal to value.
The find_if function returns an iterator i referring to the first element in the range [ first, last) that makes the predicate function object pred return true (i.e., a nonzero value), or i = last if the predicate function object pred is false for all elements in the range.
In the first function checks for element equality are made with operator!=, while in the second they are made with the function object pred.
Type requirements
Group Non-mutating sequence operations.
Time complexity Linear.
If i 
last, then the number of applications of
operator!= or pred is the size of the range
[ first, i]
; otherwise, the number of applications of
operator!= or pred is the size of the range [ first, last)
.
Space complexity Constant.
Mutative? No.
Details If i 
last, then the locations in the range
[ first, i]
are dereferenced; those in the range
( i, last]
are not. If i = last, then all of the locations in the range [ first, last) are dereferenced.
Glossary terms constant space, dereference type, dereferencing an iterator, function object, function object type, InputIterator, iterator, linear time, mutative, operator !=, Predicate, predicate, range, sequence.
Example Select here to view the source code for the example.
Implementation Select here to view source code (Copyright (C) 1994, Hewlett-Packard Company) for this algorithm.
Implementation notes A sequential forward search from first to last is performed.