find


function template
<algorithm>
template <class InputIterator, class T>
   InputIterator find ( InputIterator first, InputIterator last, const T& value );

Find value in range

Returns an iterator to the first element in the range [first,last) that compares equal to value, or last if not found.

The behavior of this function template is equivalent to:
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template<class InputIterator, class T>
  InputIterator find ( InputIterator first, InputIterator last, const T& value )
  {
    for ( ;first!=last; first++) if ( *first==value ) break;
    return first;
  }



Parameters

first, last
Input iterators to the initial and final positions in a sequence. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
value
Value to be compared to each of the elements.


Return value

An iterator to the first element in the range that matches value.
If no element matches, the function returns last.

Example

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

int main () {
  int myints[] = { 10, 20, 30 ,40 };
  int * p;

  // pointer to array element:
  p = find(myints,myints+4,30);
  ++p;
  cout << "The element following 30 is " << *p << endl;

  vector<int> myvector (myints,myints+4);
  vector<int>::iterator it;

  // iterator to vector element:
  it = find (myvector.begin(), myvector.end(), 30);
  ++it;
  cout << "The element following 30 is " << *it << endl;

  return 0;
}


Output:
The element following 30 is 40
The element following 30 is 40


Complexity

At most, performs as many comparisons as the number of elements in the range [first,last).

See also

search Find subsequence in range (function template)
binary_search Test if value exists in sorted array (function template)
for_each Apply function to range (template function)