Using an initializer_list on a map of vectors
I've been trying to initialize a map of <ints, vector<ints> >
using the new 0X standard, but I cannot seem to get the syntax correct. I'd like to make a map with a single entry with key:value = 1:<3,4>
#include <initializer_list>
#include <map>
#include <vector>
using namespace std;
map<int, vector<int> > A = {1,{3,4}};
....
It dies with the following error using gcc 4.4.3:
error: no matching function for call to std::map<int,std::vector<int,std::allocator<int> >,std::less<int>,std::allocator<std::pair<const int,std::vector<int,std::allocator<int> > > > >::map(<brace-enclosed initializer list>开发者_高级运维;)
Edit
Following the suggestion by Cogwheel and adding the extra brace it now compiles with a warning that can be gotten rid of using the -fno-deduce-init-list flag. Is there any danger in doing so?
As the comment above has mentioned, {1,{3,4}}
is a single element in the map, where the key is 1
and the value is {3,4}
. So, what you would need is { {1,{3,4}} }
.
Simplifying the error:
error: no matching function for call to map<int,vector<int>>::map(<brace-enclosed initializer list>)
Not a precise error, but somewhat helpful nonetheless.
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