about deleting in C++ STL List

[arsalan_mousavian]

i have problem with following code

Code: Select all

for ( list<int>::iterator itr = L.begin () ; itr != L.end () ; ++ itr ) 
{ 
       if ( *itr == 2 ) L.erase ( itr ) ;
}

after the first loop ( L.erase ( itr ) ) runs a runtime error occured ( iterator not incerementable )but i have no problem when using erase function outside the loop ,seems the iterator become invalid after calling erase method
any suggestions ?
Thanks
Arsalan

[Krzysztof Duleba]

That is precisely the reason. Use this code instead:

Code: Select all

for ( list<int>::iterator itr = L.begin () ; itr != L.end () ;){
    if ( *itr == 2 ) L.erase ( itr++ ) ;
    else ++itr;
}