std::deque::shrink_to_fit

 

C++

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Capacity

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deque::shrink_to_fit

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void shrink_to_fit();		(since C++11)

Requests the removal of unused capacity.

It is a non-binding request to reduce capacity to size(). It depends on the implementation if the request is fulfilled.

All iterators and references are potentially invalidated. Past-the-end iterator is also potentially invalidated.

Parameters

(none)

Type requirements

- T must meet the requirements of MoveInsertable.

Return value

(none)

Complexity

At most linear in the size of the container.

Example

Run this code

#include <deque>
 
int main() {
    std::deque<int> nums(1000, 42);
    nums.push_front(1);
    nums.pop_front();
 
    nums.clear();
 
    // nums now contains no items, but it may still be holding allocated memory. 
    // Calling shrink_to_fit will free any unused memory.
    nums.shrink_to_fit();
}

See also

size	returns the number of elements (public member function)