program Snake; const n = 6; var Mas : array [1..n, 1..n] of Integer; k : Integer;
x, y : Integer; i : Integer;
begin WriteLn; WriteLn; i := 1;
for k := 1 to n do begin x := k; y := 1;
while x > 0 do begin if ((x+y) mod 2=0) then begin Mas[y, x] := i; end else begin Mas[x, y] := i; end; i := i + 1; x := x - 1; y := y + 1 end
end;
for k := 2 to n do begin x := n; y := k;
while y <= n do begin if((x+y)mod 2=0) then begin Mas[y, x] := i; end else begin Mas[x, y] := i; end; i := i + 1; x := x - 1; y := y + 1 end
end;
for y := 1 to n do begin
for x := 1 to n do Write(Mas[x, y] : 4); WriteLn
end end.