Prototype Mismatch is an overloaded name; there are actually two mismatch functions.
template <class InputIterator1, class InputIterator2>
pair<InputIterator1, InputIterator2> mismatch(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
template <class InputIterator1, class InputIterator2, class BinaryPredicate>
pair<InputIterator1, InputIterator2> mismatch (InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, BinaryPredicate binary_pred);
Description Mismatch finds the first position where the two ranges [first1, last1) and [first2, first2 + (last1 – first1)) differ. The two versions of mismatch use different tests for whether elements differ.
The first version of mismatch finds the first iterator i in [first1, last1) such that *i != *(first2 + (i – first1)). The return value is a pair whose first element is i and whose second element is *(first2 + (i – first1)). If no such iterator i exists, the return value is a pair whose first element is last1 and whose second element is *(first2 + (last1 – first1)).
The second version of mismatch finds the first iterator i in [first1, last1) such that binary_pred(*i, * (first2 + (i – first1)) is false. The return value is a pair whose first element is i and whose second element is *(first2 + (i – first1)). If no such iterator i exists, the return value is a pair whose first element is last1 and whose second element is *(first2 + (last1 – first1)) .
Definition Defined in the standard header algorithm, and in the nonstandard backward-compatibility header algo.h.
Requirements on types For the first version:
• InputIterator1 is a model of Input Iterator.
• InputIterator2 is a model of Input Iterator.
• InputIterator1's value type is a model of Equality Comparable.
• InputIterator2's value type is a model of Equality Comparable.
• InputIterator1's value type can be compared for equality with InputIterator2's value type.
For the second version:
• InputIterator1 is a model of Input Iterator.
• InputIterator2 is a model of Input Iterator.
• BinaryPredicate is a model of Binary Predicate.
• InputIterator1's value type is convertible to BinaryPredicate's first argument type.
• InputIterator2's value type is convertible to BinaryPredicate's second argument type.
Preconditions • [first1, last1) is a valid range.
• [first2, first2 + (last2 – last1)) is a valid range.
Complexity Linear. At most last1 – first1 comparisons.
Example int A1[] = { 3, 1, 4, 1, 5, 9, 3 };
int A2[] = { 3, 1, 4, 2, 8, 5, 7 };
const int N = sizeof(A1) / sizeof(int);
pair<int*, int*> result = mismatch(A1, A1 + N, A2);
cout << 'The first mismatch is in position ' << result.first – A1 << endl;
cout << 'Values are: ' << *(result.first) << ', ' << *(result.second) << endl;
See also equal, search, find, find_if
Category: algorithms
Component type: function
Prototype Equal is an overloaded name; there are actually two equal functions.
template <class InputIterator 1, class InputIterator 2>
bool equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2);
template <class InputIterator 1, class InputIterator 2, class BinaryPredicate>
bool equal(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, BinaryPredicate binary_pred);
Description Equal returns true if the two ranges [first1, last1) and [first2, first2 + (last1 – first1)) are identical when compared element-by-element, and otherwise returns false. [1]
The first version of equal returns true if and only if for every iterator i in [first1, last1), *i == *(first2 + (i – first1)). The second version of equal returns true if and only if for every iterator i in [first1, last1), binary_pred(*i, *(first2 + (i – first1)) is true.
Definition Defined in the standard header algorithm, and in the nonstandard backward-compatibility header algo.h.
Requirements on types For the first version:
• InputIterator1 is a model of Input Iterator.
• InputIterator2 is a model of Input Iterator.
• InputIterator1's value type is a model of Equality Comparable.
• InputIterator2's value type is a model of Equality Comparable.
• InputIterator1's value type can be compared for equality with InputIterator2's value type.
For the second version:
• InputIterator1 is a model of Input Iterator.
