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| Category: algorithms | | Component type: function |
Prototype
template <class ForwardIterator, class Predicate, class T>
void replace_if(ForwardIterator first, ForwardIterator last, Predicate pred
const T& new_value)
Description
Replace_if replaces every element in the range [first, last) for which pred returns true with new_value. That is: for every iterator i, if pred(*i) is true then it performs the assignment *i = new_value.
Definition
Defined in the standard header algorithm, and in the nonstandard backward-compatibility header algo.h.
Requirements on types
-
ForwardIterator is a model of ForwardIterator.
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ForwardIterator is mutable.
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Predicate is a model of Predicate.
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ForwardIterator's value type is convertible to Predicate's argument type.
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T is convertible to Forward Iterator's value type.
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T is Assignable.
Preconditions
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[first, last) is a valid range.
Complexity
Linear. Replace_if performs exactly last - first applications of pred, and at most last - first assignments.
Example
Replace every negative number with 0.
Vector<int> V;
V.push_back(1);
V.push_back(-3);
V.push_back(2);
V.push_back(-1);
replace_if(V.begin(), V.end(), bind2nd(less<int>(), 0), -1);
assert(V[1] == 0 && V[3] == 0);
Notes
See also
replace, replace_copy, replace_copy_if
