var
a,b,s,c:real;
begin
write('a b:');readln(a,b);
c:=sqrt(sqr(a)+sqr(b));
S:=a*b/2;
writeln('c:',c,', S:',S);
end.
var
a,b,s,c:real;
procedure Sc(var a,b:real);
begin
c:=sqrt(sqr(a)+sqr(b));
S:=a*b/2;
writeln('c:',c,', S:',S);
end;
begin
write('a b:');readln(a,b);
Sc(a,b);
end.
var
a,b,s,c:real;
function Sss(var a,b:real):real;
begin
Sss:=a*b/2;
end;
function Ccc(var a,b:real):real;
begin
Ccc:=sqrt(sqr(a)+sqr(b));
end;
begin
write('a b:');readln(a,b);
S:=Sss(a,b); c:=Ccc(a,b);
writeln('c:',c,', S:',S);
end.
