The contract also has preconditions that require clients to pass in an amount greater than or equal to zero to both withdraw() and deposit().

合约还有几个前置条件，要求客户传递给withdraw()和deposit() 的参数大于或等于0。

youdao

The contract also has preconditions that require clients to pass in an amount greater than or equal to zero to both withdraw() and deposit().

合约还有几个前置条件，要求客户传递给withdraw()和deposit() 的参数大于或等于0。

youdao