1:
uses crt;
var a,b,c:real;
kt:integer;
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
begin
kt:=0;
if (a=b) and (b<>c) and (a<>c) then kt:=1;
if (b=c) and (b<>a) and (c<>a) then kt:=1;
if (a=c) and (a<>b) and (c<>b) then kt:=1;
if (a=b) and (b=c) then kt:=2;
if kt=0 then writeln('La tam giac thuong');
if kt=1 then writeln('La tam giac can');
if kt=2 then writeln('La tam giac deu');
end
else writeln('Khong la ba canh trong mot tam giac');
readln;
end.
2:
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.