std::vector::assign

Parameters

first, last

Input iterators to the initial and final positions in a sequence. The range used is [first,last), which includes all the elements between first and last, including the element pointed by first but not the element pointed by last.
The function template argument InputIterator shall be an input iterator type that points to elements of a type from which value_type objects can be constructed.

n

New size for the container.
Member type size_type is an unsigned integral type.

val

Value to fill the container with. Each of the n elements in the container will be initialized to a copy of this value.
Member type value_type is the type of the elements in the container, defined in vector as an alias of its first template parameter (T).

il

An initializer_list object. The compiler will automatically construct such objects from initializer list declarators.
Member type value_type is the type of the elements in the container, defined in vector as an alias of its first template parameter (T).

Return value

Example

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// vector assign
#include <iostream>
#include <vector>
int main ()
{
  std::vector<int> first;
  std::vector<int> second;
  std::vector<int> third;
  first.assign (7,100);             // 7 ints with a value of 100
  std::vector<int>::iterator it;
  it=first.begin()+1;
  second.assign (it,first.end()-1); // the 5 central values of first
  int myints[] = {1776,7,4};
  third.assign (myints,myints+3);   // assigning from array.
  std::cout << "Size of first: " << int (first.size()) << '\n';
  std::cout << "Size of second: " << int (second.size()) << '\n';
  std::cout << "Size of third: " << int (third.size()) << '\n';
  return 0;
}

Size of first: 7
Size of second: 5
Size of third: 3

Complexity

Iterator validity

Data races

Exception safety

See also

vector::operator=

Assign content (public member function)

vector::resize

Change size (public member function)