uses crt;
var x,i,max,n,dem,dem1,dem2,dem3,t,t1:integer;
a,b,c,d,e:array[-32000..32000]of integer;
tbca,tbcd:real;
begin
clrscr;
write('n='); readln(n);
for i:=1 to n do
begin
write('a[',i,']='); readln(a[i]);
inc(b[a[i]]);
end;
{----------------------------------cau-a----------------------------}
max:=0;
for i:=1 to n do
if max<b[a[i]] then
begin
max:=b[a[i]];
x:=a[i];
end;
writeln('phan tu co so lan xuat hien nhieu nhat trong mang la: ',x);
{--------------------------------cau-b-------------------------------}
dem:=0;
for i:=1 to n do
if a[i]>=0 then
begin
dem:=dem+1;
c[dem]:=a[i];
end;
dem1:=0;
for i:=1 to dem do
if trunc(sqrt(c[i]))=sqrt(c[i]) then inc(dem1);
writeln('so luong so chinh phuong trong day la: ',dem1);
{--------------------------------cau-c-----------------------------}
dem2:=0;
dem3:=0;
for i:=1 to n do
begin
if a[i]>0 then
begin
inc(dem2);
d[dem2]:=a[i];
end;
if a[i]<0 then
begin
inc(dem3);
e[dem3]:=a[i];
end;
end;
t:=0;
t1:=0;
for i:=1 to dem2 do
t:=t+d[i];
tbcd:=t/dem2;
for i:=1 to dem3 do
t1:=t1+e[i];
tbca:=t1/dem3;
writeln('trung binh cong cac so am la: ',tbca:4:2);
writeln('trung binh cong cac so duong la: ',tbcd:4:2);
readln;
end.

Program Hotboy ;

Uses crt;

var duong,h,l,dem,x,i,j,n,Ki:integer;

am,tb1,tb2: real;

A,B: array [1..100] of integer;

begin

clrscr;

write('Nhap so phan tu trong day :');readln(n);

for i:=1 to n do

Begin

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

End;

B[i]:=0;

For i:=1 to n do

for j:=i to n do

begin

if A[i]=B[j]then B[j]:=B[j] +1;

Ki:=B[1];

For i:=1 to n do if B[i]>Ki then Ki:=B[i];

end;

begin

if Ki=B[i]then write('so ',A[i],'xuat hien nhieu nhat');

end;

Dem:=0;

For i:=1 to n do 

   begin

    x:=trunc(sqrt(a[i]));

     if sqr(x)=a[i] then dem:=dem+1;

End; 

Writeln('co',dem,'so chinh phuong trong day');

am:=0; duong:=0; h:=0; l:=0; tb1:=0; tb2:=0;

    For i:= 1 to n do 

If A[i] <0 then 

 Begin

Am:=am+A[i];

h:=h+1;

Tb1:=am/h;

End;

for i:=1 to n do

begin

 If A[i] < 0 then

Duong:=duong+A[i];

l:=l+1;

Tb2:=duong/l;

end;

Write('trung binh cong so am la',tb1); 

Write('trung binh cong cac so duong la',tb2);

Readln

End.