Merge pull request ton-community#629 from pixelplex/storage_fee_example

update fee calculation example

docs/develop/smart-contracts/fee-calculation.md

@@ -54,10 +54,10 @@ const int RESERVE_AT_MOST = 2;
 ;;; in the case of action fail - bounce transaction. No effect if RESERVE_AT_MOST (+2) is used. TVM UPGRADE 2023-07. https://docs.ton.org/learn/tvm-instructions/tvm-upgrade-2023-07#sending-messages
 const int RESERVE_BOUNCE_ON_ACTION_FAIL = 16;
 
-() calculate_and_reserve_storage_fee(int balance, int msg_value, int workchain, int seconds, int bits, int cells) inline {
-    int to_leave_on_balance = my_ton_balance - msg_value + my_storage_due();
+() calculate_and_reserve_at_most_storage_fee(int balance, int msg_value, int workchain, int seconds, int bits, int cells) inline {
+    int on_balance_before_msg = my_ton_balance - msg_value;
     int min_storage_fee = get_storage_fee(workchain, seconds, bits, cells); ;; can be hardcoded IF CODE OF THE CONTRACT WILL NOT BE UPDATED
-    raw_reserve(max(to_leave_on_balance, min_storage_fee), RESERVE_AT_MOST);
+    raw_reserve(max(on_balance_before_msg, min_storage_fee + my_storage_due()), RESERVE_AT_MOST);
 }
 ```