/in/foo.cc: In function 'int main()':
/in/foo.cc:42:19: warning: array subscript has type 'char' [-Wchar-subscripts]
     if(ava[temp[0]]==1)
                   ^
/in/foo.cc:48:17: warning: array subscript has type 'char' [-Wchar-subscripts]
      ava[temp[0]]=1;
                 ^
/in/foo.cc:62:22: warning: array subscript has type 'char' [-Wchar-subscripts]
     ava[S.top().first]=0;
                      ^
/in/foo.cc:68:39: warning: array subscript has type 'char' [-Wchar-subscripts]
   while (!S.empty()) ava[S.top().first]=0, S.pop();
                                       ^