std::generate_n
From Cppreference
| Defined in header
<algorithm> | ||
| template< class OutputIterator, class Size, class Generator >
void generate_n( OutputIterator first, Size count, Generator g ); | ||
Assigns values, generated by given function object g, to the first count elements in the range beginning at first.
Contents |
Parameters
| first | - | the beginning of the range of elements to generate | |||||||||
| count | - | number of the elements to generate | |||||||||
| g | - | generator function object that will be called. The signature of the function should be equivalent to the following:
The type Ret must be such that an object of type OutputIterator can be dereferenced and assigned a value of type Ret. | |||||||||
Return value
(none)
Complexity
linear in the distance between first and last
Equivalent function
template< class OutputIterator, class Size, class Generator > void generate_n( OutputIterator first, Size count, Generator g ) { for( Size i = 0; i < count; i++ ) { *first++ = g(); } }
Example
The following code filld an array of int with random numbers.
#include <cstddef> #include <cstdlib> #include <iostream> #include <iterator> #include <algorithm> int main() { const std::size_t N = 5; int ar[N]; std::generate_n(ar, N, std::rand); // Using the C function rand() std::cout << "ar: "; std::copy(ar, ar+N, std::ostream_iterator<int>(std::cout, " ")); }
Output:
52894 15984720 41513563 41346135 51451456
See also
| assigns a value to some number of elements (function template) | |
| saves the result of a function in a range (function template) | |
