Uses crt;
function f(a,b:real):real;
begin
f:=sqrt(a*a+b*b)
end;
var ab,ac,dc,bd,g,p:real;
begin
clrscr;
writeln('Введите длины строн');
write('ab=');readln(ab);
write('ac=');readln(ac);
write('dc=');readln(dc);
g:=f(ab,ac);
bd:=f(g,dc);
p:=ab+ac+dc+bd;
write('Периметр=',p:0:2);
readln
end.