program biensoxe;

uses crt;

var a,b,c,d,e:real;

begin

writeln('nhap vao cac so cua bien so xe a,b,c,d,e');

readln(a,b,c,d,e);

if b=c=d=e then writr('day la bien so tu quy') else write('day khong phai la bien so chan');

end.

uses crt;

var n, a, b, c, d : longint;

begin

clrscr;

write('Nhap so : '); readln(n);

if (n >= 1111) and (n <= 9999) then

begin a := n div 1000;

b := (n - a * 1000) div 100;

c := (n - a * 1000 - b * 100) div 10;

d := n - a * 1000 - b * 100 - c * 10;

if (a = b) and (b = c) and (c = d) then

write(n,' la so tu quy') else write(n,' khong la so tu quy');

end else write(n,' khong la so tu quy');

readln

end.