program kvadratperimetr;
var a, P: real;
begin
write('Введите a:');
readln(a);
P := 4 * a;
write('P=', p);
end.
program kvadratperimetr;
var a, P: real;
begin
write('Введите a:');
readln(a);
P := 4 * a;
write('P=', p);
end.