program mas;
var i: integer;
mass: array[1..50] of integer;
begin
for i:=1 to 50 do
if i mod 2 = 0 then
mass[i]:= i
else
mass[i]:= i * (-1)
end;
writeln(mass)
end.
program mas;
var i: integer;
mass: array[1..50] of integer;
begin
for i:=1 to 50 do
begin
if i mod 2 = 0 then
mass[i]:= i
else
mass[i]:= i * (-1)
end;
writeln(mass)
end.