more update

Author: dong77

packages/loopring_v3/contracts/impl/UserStakingPool.sol

@@ -122,7 +122,10 @@ contract UserStakingPool is IUserStakingPool, Claimable
         total.balance = total.balance.sub(_amount);
         user.balance = user.balance.sub(_amount);
 
-        numAddresses -= 1;
+        if (user.balance == 0) {
+            numAddresses -= 1;
+            delete stakings[msg.sender];
+        }
 
         // transfer LRC to user
         require(