Тогда вот тебе прогга
program vidtreugolnika ;
var a, b, c : real ;
begin
readln (a, b, c);
if (a>b+c) or (b>a+c) or (c>a+b) then write ('impossible')
else if (a*a=b*b+c*c) or (b*b=a*a+c*c) or (c*c=a*a+b*b) then write ('rectangular')
else if (a*a>b*b+c*c) or (b*b>a*a+c*c) or (c*c>a*a+b*b) then write ('obtuse')
else write ('acute');
readln;
end.