How to do my program more simply? Who khow?
When I send this program - Time limit Exceed on 20 test.
Help, who can!

Program zadacha;
var a:array[1..10000] of integer; b,c,i,j,n:integer; d:array[0..100000] of longint; m:longint;
begin
readln(n);
for i:=1 to n do
 read(a[i]);

readln(m);
for i:=1 to m do begin
 read(b,c);
  for j:=b to c do
   d[i]:=d[i]+a[j];
 end;
for i:=1 to m do
writeln(d[i]);
end.