Using pair<int, int> as key for map
you need a pair as a key cout << mymap[make_pair(1,2)] << endl; What you currently have cout << mymap[(1,2)] << endl; is not the correct syntax.
mymap[make_pair(1,2)]
or, with compiler support:
mymap[{1,2}]
you need a pair as a key cout << mymap[make_pair(1,2)] << endl; What you currently have cout << mymap[(1,2)] << endl; is not the correct syntax.
mymap[make_pair(1,2)]
or, with compiler support:
mymap[{1,2}]