module FullAdder (
  input logic a,
  input logic b,
  input logic carryIn,
  output logic sum,
  output logic carryOut
);
  // Full Adder logic
  assign sum = a ^ b ^ carryIn;
  assign carryOut = (a & b) | (carryIn & (a ^ b));
endmodule

module FullAdderTestbench;
  logic a, b, carryIn;
  logic sum, carryOut;

  // Instantiate FullAdder module
  FullAdder dut (
    .a(a),
    .b(b),
    .carryIn(carryIn),
    .sum(sum),
    .carryOut(carryOut)
  );

  initial begin
    // Testcase 1
    a = 1'b0;
    b = 1'b0;
    carryIn = 1'b0;
    #10;
    $display("Testcase 1: a=%b, b=%b, carryIn=%b, sum=%b, carryOut=%b", a, b, carryIn, sum, carryOut);

    // Testcase 2
    a = 1'b1;
    b = 1'b0;
    carryIn = 1'b0;
    #10;
    $display("Testcase 2: a=%b, b=%b, carryIn=%b, sum=%b, carryOut=%b", a, b, carryIn, sum, carryOut);

    // Testcase 3
    a = 1'b1;
    b = 1'b1;
    carryIn = 1'b1;
    #10;
    $display("Testcase 3: a=%b, b=%b, carryIn=%b, sum=%b, carryOut=%b", a, b, carryIn, sum, carryOut);

    // End simulation
    $finish;
  end
endmodule