// block to calculate XY + 4*Z, where X is a 5-bit unsigned #, Y is a 4-bit unsigned  #
// and Z is a 6-bit unsigned #
module xyz(x, y, z, s);

input	[4:0] x;
input   [3:0] y;
input   [5:0] z;
output  [9:0] s;

// internal nodes within the circuit
wire	[8:0] p;
wire	t1, t2, t3, t4, t5, t6;

assign s[0] = p[0];
assign s[1] = p[1];

// structure of the circuit
mult5by4 mult_instance(x, y, p);
half_adder ha1(p[2], z[0], s[2], t1);
full_adder fa1(p[3], z[1], t1, s[3], t2);
full_adder fa2(p[4], z[2], t2, s[4], t3);
full_adder fa3(p[5], z[3], t3, s[5], t4);
full_adder fa4(p[6], z[4], t4, s[6], t5);
full_adder fa5(p[7], z[5], t5, s[7], t6);
half_adder ha2(p[8], t6, s[8], s[9]);

endmodule