program tamgiac;
uses crt;
var
a,b,c: integer;
begin
clrscr;
write('nhap vao do dai thu nhat:');readln(a);
write('nhap vao do dai thu hai:');readln(b);
write('nhap vao do dai thu ba:');readln(c);
if (a+b>c) or (b+c>a) or(c+a>b) then write ('day la do dai 3 canh cua tam giac')
else write('day ko phai la do dai 3 canh cua tam giac');
readln;
end.
uses crt;
var a,b,c:real;
begin
clrscr;
repeat
write('Nhap a='); readln(a);
write('Nhap b='); readln(b);
write('Nhap c='); readln(c);
until (a>0) and (b>0) and (c>0);
if (a+b>c) and (a+c>b) and (b+c>a) then writeln('Day la ba canh trong mot tam giac')
else writeln('Day khong la ba canh trong mot tam giac');
readln;
end.