Perform the following addition of $2$’s complement numbers. Indicate whether or not the sum overflows a $4$-bit result: $1101 + 0100$
If I add, the answer is $10001$. It is five bits, so overflows. If I convert the numbers to decimal and add, it is $13 + 4 = 17$.
However, the notes say the answer is $0001$, no overflow. And that converting results in $3 + 4 = 1$.
How can that be? Which is right?