/in/foo.cc: In function 'int main()':
/in/foo.cc:153:30: warning: 'ny' may be used uninitialized [-Wmaybe-uninitialized]
  153 |                 if(!x || x>n || !y || y>m) { ok = false; break; }
      |                    ~~~~~~~~~~^~~~~
/in/foo.cc:143:28: note: 'ny' was declared here
  143 |             for(int k=0,nx,ny;k<63;k++)
      |                            ^~
/in/foo.cc:153:17: warning: 'nx' may be used uninitialized [-Wmaybe-uninitialized]
  153 |                 if(!x || x>n || !y || y>m) { ok = false; break; }
      |                 ^~
/in/foo.cc:143:25: note: 'nx' was declared here
  143 |             for(int k=0,nx,ny;k<63;k++)
      |                         ^~