1) var
s,i:integer;
begin
s:=0;
for i:=1 to 100 do
s:=s+i;
writeln(s);
end.
2) var
s,i:integer;
begin
s:=1;
i:=2;
while i<11 do<br> begin
s:=s*i;
i:=i+2;
end;
writeln(s);
end.
3) var i,s:integer;
begin
i:=11;
s:=0;
while i<100 do<br> begin
i:=i+2;
s:=s+1;
end;
writeln(s);
end.