diff --git a/examples/kinsol/serial/kinFerTron_dns.ml b/examples/kinsol/serial/kinFerTron_dns.ml
index 525cffc..edf4bb8 100644
--- a/examples/kinsol/serial/kinFerTron_dns.ml
+++ b/examples/kinsol/serial/kinFerTron_dns.ml
@@ -115,21 +115,13 @@ let set_initial_guess2 udata =
 
 (* Print first lines of output (problem description) *)
 let print_header fnormtol scsteptol =
-  print_string "\nFerraris and Tronconi test problem\n";
-  print_string "Tolerance parameters:\n";
+  printf "\nFerraris and Tronconi test problem\n";
+  printf "Tolerance parameters:\n";
   printf "  fnormtol  = %10.6g\n  scsteptol = %10.6g\n" fnormtol scsteptol
 
 (* Print solution *)
 let print_output u = printf " %8.6g  %8.6g\n" u.{0} u.{1}
 
-let print_string_5d s i =
-  print_string s;
-  if i < 10 then print_string "    "
-  else if i < 100 then print_string "   "
-  else if i < 1000 then print_string "  "
-  else if i < 10000 then print_string " ";
-  print_int i
-
 (* Print final statistics contained in iopt *)
 (* For high NUM_REPS, the cost of OCaml printf becomes important! *)
 let print_final_stats kmem =
@@ -137,21 +129,20 @@ let print_final_stats kmem =
   let nfe  = Kinsol.get_num_func_evals kmem in
   let nje  = Kinsol.Dls.get_num_jac_evals kmem in
   let nfeD = Kinsol.Dls.get_num_func_evals kmem in
-  print_string "Final Statistics:\n";
-  print_string_5d "  nni = " nni;
-  print_string_5d "    nfe  = " nfe;
-  print_string_5d " \n  nje = " nje;
-  print_string_5d "    nfeD = " nfeD;
-  print_string " \n"
+  printf "Final Statistics:\n";
+  printf "  nni = %5d    nfe  = %5d \n" nni nfe;
+  printf "  nje = %5d    nfeD = %5d \n" nje nfeD
 
 (* MAIN PROGRAM *)
 let solve_it kmem u s glstr mset =
   print_newline ();
-  print_string (if mset==1 then "Exact Newton" else "Modified Newton");
-  if not glstr then print_newline () else print_string " with line search\n";
+  if mset == 1 then printf "Exact Newton"
+  else printf "Modified Newton";
+  if not glstr then printf "\n"
+  else printf " with line search\n";
   Kinsol.set_max_setup_calls kmem mset;
   ignore (Kinsol.solve kmem u glstr s s);
-  print_string "Solution:\n  [x1,x2] = ";
+  printf "Solution:\n  [x1,x2] = ";
   print_output (Nvector.unwrap u);
   print_final_stats kmem
 
@@ -193,9 +184,9 @@ let main () =
 
   (* --------------------------- *)
 
-  print_string "\n------------------------------------------\n";
-  print_string "\nInitial guess on lower bounds\n";
-  print_string "  [x1,x2] = ";
+  printf "\n------------------------------------------\n";
+  printf "\nInitial guess on lower bounds\n";
+  printf "  [x1,x2] = ";
   print_output u1;
 
   RealArray.blit u1 u;
@@ -218,9 +209,9 @@ let main () =
 
   (* --------------------------- *)
 
-  print_string "\n------------------------------------------\n";
-  print_string "\nInitial guess in middle of feasible region\n";
-  print_string "  [x1,x2] = ";
+  printf "\n------------------------------------------\n";
+  printf "\nInitial guess in middle of feasible region\n";
+  printf "  [x1,x2] = ";
   print_output u2;
 
   RealArray.blit u2 u;