Design a 4-to-7 decoder circuit that converts a 4-bit excess-3 into BCD on a seven segment display. There are seven outputs, each of which drives one segment of the seven segment display shown later to form the BCD digit corresponding to the input code. Assume that the display device requires a 1 to turn a segment on and a 0 to turn it off.

I'm really confused on how to work out this problem