If I have two sets of data
set<string> A;
set<string> B;
use set_intersection I am able to obtain the data in the intersection part for the two sets.
How do I print out the data in the non-intersection part for the set A and set B, respectively?
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Use std::set_difference or std::set_symmetric_difference, depending on your needs.
(I'm too tired/lazy to write an example, but hopefully it should be obvious once you've read the above links!)
Oliver Charlesworth
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set_difference will give you the results A+B-(AB), what's the way to get A-(AB) and B-(AB)? //(AB)=intersection...does that means the set_symmetric_difference? – user1830108 Jan 04 '13 at 20:44
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@user1830108: That sounds like the description of set_symmetric_difference. So you probably want set_difference. – Oliver Charlesworth Jan 04 '13 at 20:46
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Isn't the question to do with printing out data? – Peter Wood Jan 04 '13 at 21:26
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@PeterWood: On a second look, yes. But I assume that the set operation is the tricky part... – Oliver Charlesworth Jan 04 '13 at 21:26
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set_symmetric_difference puts the results into some iterable object.
So, you can copy values into an ostream by wrapping it with an ostream_iterator:
set<string> a;
set<string> b;
set_symmetric_difference(a.begin(), a.end(),
b.begin(), b.end(),
ostream_iterator<string>(cout, "\n"));
Peter Wood
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