function template
std::replace
<algorithm>
template < class ForwardIterator, class T >
void replace ( ForwardIterator first, ForwardIterator last,
const T& old_value, const T& new_value );
Replace value in range
Sets all the elements in the range
[first,last) whose current value equals
old_value to a value of
new_value.
The behavior of this function template is equivalent to:
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template < class ForwardIterator, class T >
void replace ( ForwardIterator first, ForwardIterator last,
const T& old_value, const T& new_value )
{
for (; first != last; ++first)
if (*first == old_value) *first=new_value;
}
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Parameters
- first, last
- Forward 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.
- old_value
- Value to be replaced.
- new_value
- Replacement value.
Return value
none
Example
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// replace algorithm example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main () {
int myints[] = { 10, 20, 30, 30, 20, 10, 10, 20 };
vector<int> myvector (myints, myints+8); // 10 20 30 30 20 10 10 20
replace (myvector.begin(), myvector.end(), 20, 99); // 10 99 30 30 99 10 10 99
cout << "myvector contains:";
for (vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
cout << " " << *it;
cout << endl;
return 0;
}
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Output:
myvector contains: 10 99 30 30 99 10 10 99
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Complexity
Performs as many comparisons as the number of elements in the range
[first,last).
See also
- replace_if
- Replace values in range (function template)
- replace_copy
- Copy range replacing value (function template
)
- remove
- Remove value from range (function template
)
- count
- Count appearances of value in range (function template)
- find
- Find value in range (function template)