Program Hoc24;
Var i: integer;
s: longint;
begin
s:=0;
for i:=1 to 100 do if i mod 2=1 then s:=s+i;
writeln('S=',s);
readln
end.
uses crt;
var s,i,a:integer;
begin
clrscr;
s:=0;
a:=1;
for i:=1 to 50 do
begin
s:=s+a;
a:=a+2;
end;
writeln('S=',s);
readln;
end.