program chuvi_dientich_hinhtron;
uses crt;
const pi = 3.14;
var R: integer;
cv, dt: real;
begin
clrscr;
writeln; { xuong dong }
readln ( R );
cv:= 2*R*pi;
writeln ( ' chu vi = ' , cv : 8:2 );
dt:=R*R*pi;
writeln ( 'dien tich = ', dt :8:2 );
readln;
end.
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