patch 7.4.823
Problem:    Cursor moves after CTRL-A on alphabetic character.
Solution:   (Hirohito Higashi, test by Christian Brabandt)
diff --git a/src/ops.c b/src/ops.c
index f53567b..62d88a7 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -5584,6 +5584,7 @@
 	    did_change = TRUE;
 	    (void)del_char(FALSE);
 	    ins_char(firstdigit);
+	    curwin->w_cursor.col = col;
 	}
 	else
 	{