Program BTT;
Uses crt;
Var a,b,c: extended;
Begin
        Clrscr;
        Write('Nhap a, b, c: '); Readln(a,b,c);
        If (a+b>c) and (a+c>b) and (b+c>a) and (a<>0) and (b<>0) and (c<>0) and (sqr(a)+sqr(b)=sqr(c)) or (sqr(b)+sqr(c)=sqr(a)) or (sqr(a)+sqr(c)=sqr(b) then Write('Tam giac vuong');
        If (a+b<c) or (a+c<b) or (b+c<a) or (a=0) or (b=0) or (c=0) or (sqr(a)+sqr(b)<>sqr(c)) or (sqr(b)+sqr(c)<>sqr(a)) or (sqr(a)+sqr(c)<>sqr(b)) then Write('Khong phai tam giac vuong');
        Readln
End.

if sqr(a) + sqr(b) = sqr(c) then write('Tam giac vuong');

if sqr(b) + sqr(c) = sqr(a) then write('Tam giac vuong');

if sqr(a) + sqr(c) = sqr(t) then write('Tam giac vuong');