In file included from /usr/include/c++/6/backward/hash_map:60:0,
from /in/foo.cc:16:
/usr/include/c++/6/backward/backward_warning.h:32:2: warning: #warning This file includes at least one deprecated or antiquated header which may be removed without further notice at a future date. Please use a non-deprecated interface with equivalent functionality instead. For a listing of replacement headers and interfaces, consult the file backward_warning.h. To disable this warning use -Wno-deprecated. [-Wcpp]
#warning \
^~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:53:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<e.size();j++)
~^~~~~~~~~
/in/foo.cc:81:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<e.size();i++)
~^~~~~~~~~