/in/foo.cc:55:11: warning: multi-character character constant [-Wmultichar]
     if(a=='min')
           ^~~~~
/in/foo.cc:61:11: warning: multi-character character constant [-Wmultichar]
     if(a=='hour')
           ^~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:55:11: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
     if(a=='min')
           ^~~~~
/in/foo.cc:61:11: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
     if(a=='hour')
           ^~~~~~