1:
uses crt;
var a:array[1..30]of integer;
i,n,dem:integer;
begin
clrscr;
write('Nhap n='); readln(n);
for i:=1 to n do
begin
write('A[',i,']='); readln(a[i]);
end;
dem:=0;
for i:=1 to n do
if a[i] mod 3=0 then inc(dem);
writeln(dem);
readln;
end.
2:
uses crt;
var a:array[1..30]of integer;
i,n,x,dem:integer;
begin
clrscr;
write('Nhap n='); readln(n);
for i:=1 to n do
begin
write('A[',i,']='); readln(a[i]);
end;
write('Nhap x='); readln(x);
dem:=0;
for i:=1 to n do
if a[i]=x then inc(dem);
writeln('So phan tu bang ',x,' la: ',dem);
for i:=1 to n do
if a[i]=x then write(i:4);
readln;
end.