program mn;
uses crt;
var a:array[1..20]of integer;
n,k1,k2,i,s:integer;
BEGIN
ClrScr;
Write('n:');
readln(n);
for i:=1 to n do
begin
a[i]:=random(100);
Write(a[i],' ');
end;
writeln;
Write('k1,k2:');
readln(k1,k2);
for i:=k1 to k2 do
s:=s+a[i];
Writeln(s);
readln;
END.