1:
program Hello;
uses crt;
var s:string;
i,d:integer;
begin
clrscr;
write('Nhap xau: ');
readln(s);
for i:= 1 to length(s) do
if s[i] = 'A' then
inc(d);
writeln('Co ', d, ' ky tu A.');
end.
===============================
2:
program Hello;
uses crt;
var a,b:real;
f:text;
begin
clrscr;
assign(f,'dulieu.inp');
readln(f,a,b);
close(f);
writeln('Trung binh cong: ', (a+b)/2:2:2);
writeln('Trung binh nhan: ', sqrt(a*b):2:2)
end.
