Var a:array[1..20] of integer;
max,min:integer;
tbc:real;
Begin
For i:=1 to 20 do
Begin
Write('Nhap so thu ',i,' = ');readln(a[i]);
End;
Max:=a[1];
Min:=a[1];
For i:=2 to 20 do
Begin
If a[i] > max then max:=a[i];
If a[i] < min then min:=a[i];
End;
tbc:=(max+min)/2;
Writeln('So lon nhat la ',max);
Writeln('So nho nhat la ',min);
Write('Trung binh cong la ',tbc:10:2);
Readln;
End.