As the title said. I'm new to c++. So i wanted to make a map with pair of int as the key and boolean as the value
map <pair<int,int>,bool>.
how do i assign the value and access it?
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1Same way you do any other map. You pass a pair to it using `[]` or `find`. – NathanOliver Mar 14 '17 at 11:52
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so mymap[int,int]=value. ? – Fandy Putra Mar 14 '17 at 11:54
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No. How would you create a `pair`, pass a pair to a function? – NathanOliver Mar 14 '17 at 11:55
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i'm a little confused. how do i declare the map and use it(assign value, get the value)? – Fandy Putra Mar 14 '17 at 11:57
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1@FandyPutra e.g. like [this](http://coliru.stacked-crooked.com/a/d9ae369118fa3fee) – W.F. Mar 14 '17 at 11:59
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1kind of a dupe of [this](http://stackoverflow.com/questions/3277172/using-pair-as-key-in-a-map-c-stl) and [this](http://stackoverflow.com/questions/15016646/using-pairint-int-as-key-for-map) – NathanOliver Mar 14 '17 at 11:59
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Possible duplicate of [Using pair
as key for map](http://stackoverflow.com/questions/15016646/using-pairint-int-as-key-for-map) – W.F. Mar 14 '17 at 12:03 -
Possible duplicate of [Using pair as key in a map (C++ / STL)](http://stackoverflow.com/questions/3277172/using-pair-as-key-in-a-map-c-stl) – Reins Mar 14 '17 at 12:40
2 Answers
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You'll need to pass one std::pair<int,int> object (your comment suggests passing two int objects, but that's no pair yet.)
You can create a std::pair<int,int> like this: std::pair<int,int> {5,7} or figure out the types from the two arguments to std::make_pair(5, 7).
MSalters
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The first argument in
map <pair<int,int>, bool> mp;
is a key of pair. Therefore you can assign a value and access it as -
mp[{1,2}] = true;
Dev Pahuja
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