4-variable(1)(2)(3)

题目如下：

Implement the circuit described by the Karnaugh map below.

Implement the circuit described by the Karnaugh map below.

Implement the circuit described by the Karnaugh map below.

代码如下：

module top_module(
    input a,
    input b,
    input c,
    input d,
    output out  ); 
	assign out = ~a & ~d | ~b & ~c | b & c & d | a & c & d;
endmodule

module top_module(
    input a,
    input b,
    input c,
    input d,
    output out  ); 
	assign out =  a | (~a&~b&c);
endmodule

module top_module(
    input a,
    input b,
    input c,
    input d,
    output out  ); 
	assign out = ~a & b & ~c & ~d | a & ~b & ~c & ~d | 
        		 ~a & ~b & ~c & d | a & b & ~c & d | 
        		 ~a & b & c & d | a & ~b & c & d | 
        		 ~a & ~b & c & ~d | a & b & c & ~d;
endmodule