fill_n
Assigns a new value to a specified number of elements in a range beginning with a particular element.
template<class OutputIterator, class Size, class Type>
void fill_n(
OutputIterator _First,
Size _Count,
const Type& _Val
);
Parameters
_First
An output iterator addressing the position of the first element in the range to be assigned the value _Val._Count
A signed or unsigned integer type specifying the number of elements to be assigned the value._Val
The value to be assigned to elements in the range [_First, _First + _Count).
Remarks
The destination range must be valid; all pointers must be dereferenceable, and the last position is reachable from the first by incrementation. The complexity is linear with the size of the range.
fill_n has two related forms:
For information on how these functions behave, see Checked Iterators.
Example
// alg_fill_n.cpp
// compile with: /EHsc
#include <vector>
#include <algorithm>
#include <iostream>
int main() {
using namespace std;
vector <int> v1;
vector <int>::iterator Iter1;
int i;
for ( i = 0 ; i <= 9 ; i++ )
v1.push_back( 5 * i );
cout << "Vector v1 = ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")" << endl;
// Fill the last 5 positions with a value of 2
fill_n( v1.begin( ) + 5, 5, 2 );
cout << "Modified v1 = ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")" << endl;
}
Output
Vector v1 = ( 0 5 10 15 20 25 30 35 40 45 )
Modified v1 = ( 0 5 10 15 20 2 2 2 2 2 )
Requirements
Header: <algorithm>
Namespace: std