Fix a comment in autodiff.h

Change-Id: I613e537c834e3f29cd92808c65ddb74f112974cc

include/ceres/internal/autodiff.h

diff --git a/include/ceres/internal/autodiff.h b/include/ceres/internal/autodiff.h
index 4b97b5b..3505c85 100644
--- a/include/ceres/internal/autodiff.h
+++ b/include/ceres/internal/autodiff.h
@@ -206,9 +206,9 @@
 // If one having three parameter blocks with dimensions (3, 2, 4), the call
 // Make1stOrderPerturbations<integer_sequence<3, 2, 4>::Apply(params, x);
 // will result in the following calls to Make1stOrderPerturbation:
-// Make1stOrderPerturbation<0, 0, 3>::Apply(params[0], x + 0);
-// Make1stOrderPerturbation<0, 3, 2>::Apply(params[1], x + 3);
-// Make1stOrderPerturbation<0, 5, 4>::Apply(params[2], x + 5);
+// Make1stOrderPerturbation<0, 3, 0>::Apply(params[0], x + 0);
+// Make1stOrderPerturbation<0, 2, 3>::Apply(params[1], x + 3);
+// Make1stOrderPerturbation<0, 4, 5>::Apply(params[2], x + 5);
 template <typename Seq, int ParameterIdx = 0, int Offset = 0>
 struct Make1stOrderPerturbations;