Книга: Standard Template Library Programmer
replace_copy_if
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replace_copy_if
Category: algorithms
Component type: function
Prototype
template <class InputIterator, class OutputIterator, class Predicate, class T>
OutputIterator replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T& new_value)
Description
Replace_copy_if copies elements from the range [first, last) to the range [result, result + (last-first)), except that any element for which pred is true is not copied; new_value is copied instead. More precisely, for every integer n such that 0 <= n < last-first, replace_copy_if performs the assignment *(result+n) = new_value if pred(*(first+n)) , and *(result+n) = *(first+n) otherwise.
Definition
Defined in the standard header algorithm, and in the nonstandard backward-compatibility header algo.h.
Requirements on types
• InputIterator is a model of Input Iterator.
• OutputIterator is a model of Output Iterator.
• Predicate is a model of Predicate.
• T is convertible to Predicate's argument type.
• T is Assignable.
• T is convertible to a type in OutputIterator's set of value types.
Preconditions
• [first, last) is a valid range.
• There is enough space in the output range to store the copied values. That is, [result, result + (last-first)) is a valid range.
• result is not an iterator within the range [first, last).
Complexity
Linear. Replace_copy performs exactly last – first applications of pred and exactly last – first assignments.
Example
Copy elements from one vector to another, replacing all negative numbers with 0.
vector<int> V1;
V1.push_back(1);
V1.push_back(-1);
V1.push_back(-5);
V1.push_back(2);
vector<int> V2(4);
replace_copy_if(V1.begin(), V1.end(), V2.begin(), bind2nd(less<int>(), 0), 0);
assert(V[0] == 1 && V[1] == 0 && V[2] == 0 && V[3] == 2);
See also
copy, replace, replace_if, replace_copy