for...do
program tong_so_nguyen;
uses crt;
var a,b,i:integer;
t:longint;
begin
clrscr;
write('Nhap a: '); readln(a);
write('Nhap b: ); readln(b);
t:=0;
for i:=a to b do
t:=t+i;
write('Tong cac so giua 2 so do la: ',t);
readln;
end.
while...do
program tong_so_nguyen;
uses crt;
var a,b,i:integer;
t:longint;
begin
clrscr;
write('Nhap a: '); readln(a);
write('Nhap b: '); readln(b);
i:=a;
while i<=b do
begin
t:=t+i;
i:=i+1;
end;
write('Tong cac so o giua a va b la: ',t);
readln;
end.
