/in/foo.cc: In function 'int main()':
/in/foo.cc:27:37: warning: array subscript has type 'char' [-Wchar-subscripts]
   l[++cnt]=(line){x,y,x+len*dx[ch[1]],y+len*dy[ch[1]]};
                                     ^
/in/foo.cc:27:53: warning: array subscript has type 'char' [-Wchar-subscripts]
   l[++cnt]=(line){x,y,x+len*dx[ch[1]],y+len*dy[ch[1]]};
                                                     ^
/in/foo.cc:28:30: warning: array subscript has type 'char' [-Wchar-subscripts]
   hx[++cntx]=(x+=len*dx[ch[1]]);hx[++cntx]=x+1;
                              ^
/in/foo.cc:29:30: warning: array subscript has type 'char' [-Wchar-subscripts]
   hy[++cnty]=(y+=len*dy[ch[1]]);hy[++cnty]=y+1;
                              ^