init units and bins, fix 5

calc_tb.sv

@@ -20,7 +20,13 @@ covergroup cg @(posedge clk);
     bins S_MUL = {3};
     bins S_DIV = {4};
   }
-  c2: coverpoint calc_dut.STATE_C;
+  c2: coverpoint calc_dut.STATE_C {
+    bins S_IDLE = {0};
+    bins S_ADD = {1};
+    bins S_SUB = {2};
+    bins S_MUL = {3};
+    bins S_DIV = {4};
+  }
 endgroup: cg
 
 cg cover_inst = new; // instatiate the cover model