std::deque<T,Allocator>::resize

Resizes the container to contain count elements, does nothing if count == size().

# Declarations

void resize( size_type count );

void resize( size_type count, const value_type& value );

# Parameters

count: new size of the container
value: the value to initialize the new elements with

# Notes

If value-initialization in overload (1) is undesirable, for example, if the elements are of non-class type and zeroing out is not needed, it can be avoided by providing a custom Allocator::construct.

# Example

#include <deque>
#include <iostream>
 
void print(auto rem, const std::deque<int>& c)
{
    for (std::cout << rem; const int el : c)
        std::cout << el << ' ';
    std::cout << '\n';
}
 
int main()
{
    std::deque<int> c = {1, 2, 3};
    print("The deque holds: ", c);
 
    c.resize(5);
    print("After resize up to 5: ", c);
 
    c.resize(2);
    print("After resize down to 2: ", c);
 
    c.resize(6, 4);
    print("After resize up to 6 (initializer = 4): ", c);
}

# Defect reports

DR	Applied to	Behavior as published	Correct behavior
LWG 679	C++98	resize() passed value by value	passes by const reference
LWG 1418	C++98	the behavior of resize(size()) was not specified	specified
LWG 2033	C++11	1. elements were removed by using erase()[1]2. T was not required to be MoveInsertable	1. uses pop_back()2. required
LWG 2066	C++11	overload (1) did not have the exceptionsafety guarantee of overload (2)	added
LWG 2160	C++11	elements were removed by using pop_back()[2]due to the resolution of LWG 2033	does not specify the methodof removing elements