Having a hard time with this one, not sure what I am doing wrong but i know its not right.

Work Design Problem 1, except use 4-2-1-8 code instead of 8-4-2-1 code. For example, in 4-2-1-8 code, 9 is represented by 0011. Also, change the representations of digits 6 and 9 to the opposite form given in Problem 1. Any solution with 20 or fewer gates and inverters (not counting the four inverters for the inputs) is acceptable.

Problem 1

Design an 8-4-2-1 BCD code converter to drive a seven-segment indicator. The four inputs to the converter circuit (A, B, C, and D in the figure above) represent an 8-4-2-1 binary-coded-decimal digit. Assume that only input combinations representing the digits 0 through 9 can occur as inputs so that the combinations 1010 through 1111 are dont-cares. Design your circuit using only two-, three-, and four-input NAND gates and inverters. Try to minimize the number of gates required. The variables A, B, C, and D will be available from toggle switches.

Seven-Segment Indicator 4-01 4- inputs Fro?B_ Circuit to be -o 4 Switches ID Design- Seven-Segment Indicator 4-01 4- inputs Fro?B_ Circuit to be -o 4 Switches ID Design