public member function
<map>
bool empty() const noexcept;
Test whether container is empty
Returns whether the multimap container is empty (i.e. whether its size is 0).
This function does not modify the container in any way. To clear the content of a multimap container, see multimap::clear.
Return Value
true if the container size is 0, false otherwise.
Example
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// multimap::empty
#include <iostream>
#include <map>
int main ()
{
std::multimap<char,int> mymultimap;
mymultimap.insert (std::pair<char,int>('b',101));
mymultimap.insert (std::pair<char,int>('b',202));
mymultimap.insert (std::pair<char,int>('q',505));
while (!mymultimap.empty())
{
std::cout << mymultimap.begin()->first << " => ";
std::cout << mymultimap.begin()->second << '\n';
mymultimap.erase(mymultimap.begin());
}
return 0;
}
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Output:
b => 101
b => 202
q => 505
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Iterator validity
No changes.
Data races
The container is accessed.
No contained elements are accessed: concurrently accessing or modifying them is safe.
Exception safety
No-throw guarantee: this member function never throws exceptions.