museum.cpp: In function 'void score(std::map<std::__cxx11::basic_string<char>, int>&, int, int)':
museum.cpp:9:11: error: 'to_string' was not declared in this scope
s.append(to_string(i));
^~~~~~~~~
museum.cpp:9:11: note: suggested alternatives:
In file included from /usr/include/c++/7/string:52:0,
from museum.cpp:3:
/usr/include/c++/7/bits/basic_string.h:6454:3: note: 'std::__cxx11::to_string'
to_string(long double __val)
^~~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6454:3: note: 'std::__cxx11::to_string'