C++ Tutorial/map multimap/multimap erase

Материал из C\C++ эксперт
Перейти к: навигация, поиск

Erase an element given an iterator from the multimap

#include <map>
#include <iostream>
#include <string>
using namespace std;
typedef multimap <int, string> MULTIMAP_INT_STRING;
int main ()
{
    MULTIMAP_INT_STRING  mmapIntToString;
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type (3, "Three"));
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type(45, "Forty Five"));
    // Erase an element given an iterator from the multimap
    MULTIMAP_INT_STRING::iterator iElementLocator = mmapIntToString.find(45);
    if (iElementLocator != mmapIntToString.end ())
    {
        mmapIntToString.erase (iElementLocator);
        cout << "Erased a pair with 45 as key using an iterator" << endl;
    }
    MULTIMAP_INT_STRING::const_iterator iPairLocator;
    
    // Print the contents of the multimap to the screen
    for ( iPairLocator = mmapIntToString.begin ()
        ; iPairLocator != mmapIntToString.end ()
        ; ++ iPairLocator )
    {
        cout << "Key: " << iPairLocator->first;
        cout << ", Value: " << iPairLocator->second.c_str () << endl;
    }
    return 0;
}

Erase an element with key as -1 from the multimap

#include <map>
#include <iostream>
#include <string>
using namespace std;
typedef multimap <int, string> MULTIMAP_INT_STRING;
int main ()
{
    MULTIMAP_INT_STRING  mmapIntToString;
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type (3, "Three"));
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type(45, "Forty Five"));
    // Eraseing an element with key as -1 from the multimap
    if (mmapIntToString.erase (-1) > 0)
        cout << "Erased all pairs with -1 as key." << endl;
    MULTIMAP_INT_STRING::const_iterator iPairLocator;
    // Print the contents of the multimap to the screen
    for ( iPairLocator = mmapIntToString.begin ()
        ; iPairLocator != mmapIntToString.end ()
        ; ++ iPairLocator )
    {
        cout << "Key: " << iPairLocator->first;
        cout << ", Value: " << iPairLocator->second.c_str () << endl;
    }
    return 0;
}

Erase a range from the multimap

#include <map>
#include <iostream>
#include <string>
using namespace std;
typedef multimap <int, string> MULTIMAP_INT_STRING;
int main ()
{
    MULTIMAP_INT_STRING  mmapIntToString;
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type (3, "Three"));
    mmapIntToString.insert (MULTIMAP_INT_STRING::value_type(45, "Forty Five"));
    // Erase a range from the multimap...
    cout << "Erasing the range of pairs with 1000 as key." << endl;
    mmapIntToString.erase ( mmapIntToString.lower_bound (1000)
        , mmapIntToString.upper_bound (1000) );
    cout << endl;
    cout << "The multimap now contains " << mmapIntToString.size ();
    cout << " key-value pair(s)." << "They are: " << endl;
    MULTIMAP_INT_STRING::const_iterator iPairLocator;
    // Print the contents of the multimap to the screen
    for ( iPairLocator = mmapIntToString.begin ()
        ; iPairLocator != mmapIntToString.end ()
        ; ++ iPairLocator )
    {
        cout << "Key: " << iPairLocator->first;
        cout << ", Value: " << iPairLocator->second.c_str () << endl;
    }
    return 0;
}
Источник — «http://cppe.ru/index.php?title=C%2B%2B_Tutorial/map_multimap/multimap_erase&oldid=2079»