replace


Category: algorithms	Component type: function

Prototype

template <class ForwardIterator, class T>
void replace(ForwardIterator first, ForwardIterator last, const T& old_value,
             const T& new_value)

Description

Replace replaces every element in the range [first, last) equal to old_value with new_value. That is: for every iterator i, if *i == old_value 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 Forward Iterator.
ForwardIterator is mutable.
T is convertible to ForwardIterator's value type.
T is Assignable.
T is EqualityComparable, and may be compared for equality with objects of ForwardIterator's value type.

Preconditions

[first, last) is a valid range.

Complexity

Linear. Replace performs exactly last - first comparisons for equality, and at most last - first assignments.

Example

vector<int> V;
V.push_back(1);
V.push_back(2);
V.push_back(3);
V.push_back(1);

replace(V.begin(), V.end(), 1, 99);
assert(V[0] == 99 && V[3] == 99);