uses crt;
var a:array[1..10]of longint; i,x,dem:longint;
begin
 clrscr;
  for i:=1 to 10 do
        begin
         write('nhap so thu ',i,':');readln(a[i]);
         while(a[i]>20)and(a[i]<0) do
                begin
                 write('nhap lai so thu ',i,':');readln(a[i]);
                end;
        end;
  write('nhap so x:');readln(x);
  dem:=0;
  for i:=1 to 10 do if(a[i]=x)then inc(dem);
  write(dem);
 readln
end.

uses crt;
var a:array[1..10]of integer;
    i,x,d: integer;
begin
clrscr;
for i:=1 to 10 do
begin
write('a[',i,']='); readln(a[i]);
while(a[i]>20) and (a[i]<0) do
begin
write('Nhap lai a[',i,']='); readln(a[i]);
end; end;
write('Nhap x:'); readln(x);
d:=0;
for i:=1 to 10 do if(a[i]=x)then d:=d+1;
write(d);
readln
end.