I could nt understand the following clearly.so i ask you another example
Let's use a bank application program as an example. Assuming that the program has multiple threads running, with each
thread connecting one ATM system, and you have a saving account in the bank with $100.00, now you and your friend are going to two different ATMs at about the same time, and trying to withdraw $50.00 from your account, what do you think it will happen?
Time 01:01 02:01 03:01 04:01
+----------+---------+---------+-------
Thread 1 Get Set
Action You Account Account You
Withdraw Balance Balance Receive
$50.00 $100.00 $50.00 $50.00
Time 01:02 02:02 03:02 04:02
-+----------+---------+-----------+------
Thread 2 Get Set
Action Friend Account Account Friend
Withdraw Balance Balance Receive
$50.00 $100.00 $50.00 $50.00
Time 01:01 02:01 03:01 04:01
-----------++--------++--------++------
Account $100.00 $100.00 $50.00 $50.00