Deleting Elements of Vector Inside a Loop

Question

I have a vector, words, of type: vector<string>. I am trying to delete every element of words that is not contained in the vector<string> called largest_family, but can't seem to accomplish this. Any help is appreciated.

vector<string>::iterator it = words.begin();
for (int i = 0; i < words.size(); i++)
{
    if (find(largest_family.begin(), largest_family.end(), words[i]) == largest_family.end())
    {
        words.erase(it);
    }
    else
    {
        it++;
    }
}

score 1 · Accepted Answer · edited May 23 '17 at 11:48

1

The right way to perform such task is:

for (vector<string>::const_iterator it = words.begin(); it != words.end();)
{
    if (find(largest_family.begin(), largest_family.end(), *it) == largest_family.end())
    {
        it = words.erase(it);
    }
    else
    {
        ++it;
    }
}

There are many related topics on SO: for example this or this.

edited May 23 '17 at 11:48

Community

1
1

answered Oct 21 '16 at 20:57

Edgar Rokjān

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You should call `cbegin()` and `cend()` if you're going to use `const_iterator`. – Hatted Rooster Oct 21 '16 at 21:09
@GillBates it depends on the standard. I don't see *c++11* tag here, that's why I didn't use them. – Edgar Rokjān Oct 21 '16 at 21:10
@EdgarRokyan C++ is C++14 now, and C++ means that. I see no C++03 tag. – juanchopanza Oct 21 '16 at 21:26

Deleting Elements of Vector Inside a Loop

1 Answers1