编辑代码

program triangle;
begin
  var a,b,c;
  if a+b>c && a+c>b && b+c>a then
    begin
      write('can form triangle.')
      if a==b && a==c then
         write('equilateral triangle.')
      else if a==b | a==c | b==c then
         write('isosceles triangle.')
      else if sqrt(sqr(a)+sqr(b))==c | sqrt(sqr(a)+sqr(c))==b | sqrt(sqr(b)+sqr(c))==a then
         write('right triangle.')
    end;
  else
    write('cannot form triangle.')
end.