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std::basic_string::shrink_to_fit

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.

Parameters

(none).

Return value

(none).

Complexity

Constant.

Example

#include <iostream>
#include <string>
 
int main()
{
    std::string s;
    std::cout << "Default-constructed capacity is " << s.capacity() << '\n';
    s.resize(100);
    std::cout << "Capacity of a 100-element string is " << s.capacity() << '\n';
    s.clear();
    std::cout << "Capacity after clear() is " << s.capacity() << '\n';
    s.shrink_to_fit();
    std::cout << "Capacity after shrink_to_fit() is " << s.capacity() << '\n';
}

Output:

Default-constructed capacity is 0
Capacity of a 100-element string is 100
Capacity after clear() is 100
Capacity after shrink_to_fit() is 0

See also

 returns the number of characters
(public member function)
returns the number of characters that can be held in currently allocated storage
(public member function)

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