var n,i,j,d:longint;
s,t:double;
a:array[1..1000] of double;
begin
readln(n);
for i:=1 to n do
read(a[i]);
for i:=1 to n do
if (a[i]>=0) then d:=d+1
else s:=s+a[i];
for i:=1 to n do
for j:=i+1 to n do
if (a[i]>a[j]) then begin t:=a[i];
a[i]:=a[j];
a[j]:=t; end;
writeln(d);
for i:=1 to n do
write(a[i]:5:2,' ');
writeln;
write(s:5:2);
end.

uses crt;
var a:array[1..50]of real;
i,n,dem,j:integer;
tam,t:real;
begin
clrscr;
write('n='); readln(n);
for i:=1 to n do
begin
write('a[',i,']='); readln(a[i]);
end;
{-----------------------------cau-a--------------------------------}
dem:=0;
for i:=1 to n do
if a[i]>0 then inc(dem);
writeln('so phan tu duong cua day la: ',dem);
{-----------------------------cau-b---------------------------------}
for i:=1 to n-1 do
for j:=i+1 to n do
if a[i]>a[j] then
begin
tam:=a[i];
a[i]:=a[j];
a[j]:=tam;
end;
writeln('day tang dan cua mang la: ');
for i:=1 to n do
write(a[i]:4:2,' ');
{-----------------------------cau-c-----------------------------------}
writeln;
t:=0;
for i:=1 to n do
if a[i]<0 then t:=t+a[i];
writeln('tong cac phan tu am trong day la: ',t:4:2);
readln;
end.

Program HOC24;

var a: array[1..100] of integer;

i,n,d: integer;

t: longint;

begin

write('Nhap so phan tu n='); readln(n);

d:=0;

for i:=1 to n do

begin

write('a[',i,']='); readln(a[i]);

if a[i]>0 then

begin

d:=d+1;

t:=t+a[i];

end;

end;

write('Trung binh cong cac so duong trong mang la :',t/d:1:2);

readln

end.

cảm ơn ạ ^^

1/write('So so can nhap: ');
readln(n);
{******Nhap mang a gom cac so nguyen duong < 1000********}
for i:=1 to n do
begin
write('Nhap so thu ', i);
readln(a[i]);
while a[i] > 1001 do
(chỗ này đề bài hơi khó hiểu, nếu nguyên dương thì cần gì trị tuyệt đối, nhưng nếu cả số nguyên âm nữa thì bạn phải dùng đk abs(a[i])>1001)
begin
write('Ban phai nhap lai so nho hon 1001: ');
readln(a[i]);
end;
end;
kt:=true;
{******* In mang cac so da nhap*******}
for i:=1 to n do
begin
write(a[i]: 6);
if i mod 8=0 then writeln;
end;
{***** Kiem tra day co phai la cap so cong ko"*****}
for i:=1 to n-2 do
if a[i]+a[i+2]<> 2* a[i+1] then kt:= false;
if kt then write('Day la cap so cong')
else writeln('Day ko la cap so cong');
readln;
END.

program bai1;

var a:array[1..100] of longint;

i,n:longint;

begin

wrtie('N= ');readln(n);

for i:=1 to n do

begin

write('A[',i,']= ');

readln(a[i]);

end;

write('Cac phan tu trong day lon hoc 10 la ');

for i:=1 to n do

if a[i]>10 then write(a[i],' ');

readln

end.

uses crt;

var a:array[1..250]of real;

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) and (a[i] mod 5=0) then inc(dem);

writeln('So phan tu chia het cho 3 va chia het cho 5 la: ',dem);

readln;

end.

1/

program uoc;

uses crt;

var n,i,dem,x:word;

a:array[1..20] of longint;

begin

clrscr;

write('nhap so phan tu cua day:') ;readln(n);

while n>20 do

begin

write('nhap lai so phan tu thoa man toi da la 20 phan tu:');

readln(n);

end;

writeln('nhap cac phan tu cua mang:');

for i:=1 to n do

begin

write('a[',i,']='); readln(a[i]);

end;

write('nhap so nguyen x:'); readln(x);

dem:=0;

for i:=1 to n do

if x mod a[i] =0 then

begin

dem:=dem+1;

writeln(a[i],' la uoc cua ',x);

end;

if dem=0 then writeln('khong co phan tu la uoc cua ',x)

else write('co ',dem,' phan tu la uoc cua ',x);

readln;

end.

k thấy rõ bạn ơi