Var S : Array [0..1,1..3000] of Byte;
    N,M,I,J,C : Longint;
a:string;

Begin
  while not (eof) do
begin
readln (a);
  Read(n,m);   C := 1;
  For J:=1 to N do S[1-C,J] := 0;
  For I:=1 to M do     Begin
      For J:=1 to N do Read(S[C,J]);
  For J:=1 to N-1 do
If (((S[1-C,J]=0)and(S[1-C,J+1]=1)and(S[C,J]=1)and(S
[C,J+1]=1))or
((S[1-C,J]=1) and (S[1-C,J+1]=0) and (S[C,J]=1) and (S
[C,J+1]=1)) or
((S[1-C,J]=1) and (S[1-C,J+1]=1) and (S[C,J]=0) and (S
[C,J+1]=1)) or
(S[1-C,J]=1) and (S[1-C,J+1]=1) and (S[C,J]=1) and (S[C,J+1]=0)) then
      Begin
      writeln;
   readln;
    writeln (a);

        Writeln('No');
        break;
       End;
   C := 1 - C;
    End;
      writeln;
   readln;
    writeln (a);

  Writeln('Yes');
end;
End.

Read(m,n) !!!