JuniorTheoryCommon

What happens when this program is compiled and run?

int n = 5;
object box = n;
Console.WriteLine(box);
long big = (long)box;
Console.WriteLine(big);

5, then an InvalidCastException

Expecting 5 twice: unboxing is not a number conversion; a boxed int comes out as int, not as long, so (long)box throws. Write long big = (int)box;.
Expecting a compile error: the compiler cannot see what an object holds, so the cast is checked only when the program reaches that line.

How would you change the line with (long)box so that the program prints 5 twice?
Why does object box = n; need no cast, while int back = box; does not compile?

JuniorTheoryCommon

int n = 5;
object box = n;
Console.WriteLine(box);
long big = (long)box;
Console.WriteLine(big);

5, then an InvalidCastException

Expecting 5 twice: unboxing is not a number conversion; a boxed int comes out as int, not as long, so (long)box throws. Write long big = (int)box;.
Expecting a compile error: the compiler cannot see what an object holds, so the cast is checked only when the program reaches that line.

How would you change the line with (long)box so that the program prints 5 twice?
Why does object box = n; need no cast, while int back = box; does not compile?