C++ Deque Library - assign() Function

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Description

The C++ function std::deque::assign() assign new value to deque by replacing old ones. New element are constructed in range of first to last.

Declaration

Following is the declaration for std::deque::assign() function form std::deque header.

C++98

template <class InputIterator>
void assign (InputIterator first, InputIterator last);

C++11

template <class InputIterator>
void assign (InputIterator first, InputIterator last);

Parameters

• first − Input iterator to the initial position in range.

• last − Input iterator to the final position in range.

Return value

None

Exceptions

If range specified by first and last is not valid then result is undefined.

Time complexity

Linear i.e. O(n)

Example

The following example shows the usage of std::deque::assign() function.

#include <iostream>
#include <deque>

using namespace std;

int main(void) {

   deque<int> d1 = {1, 2, 3, 4, 5};
   deque<int> d2;

   d2.assign(d1.begin(), d1.begin() + 3);

   cout << "Contents of deque d2 are" << endl;

   for (int i = 0; i < d2.size(); ++i)
      cout << d2[i] << endl;

   return 0;
}

Let us compile and run the above program, this will produce the following result −

Contents of deque d2 are
1
2
3