Felix Cai 2021.1.5
Fixed
Fixed
Fixed
Fixed
(-) To do later
(+) SafeMath lib is used in some "dangerous" places, such as multiplication of votes. For the part in the context that has been checked and will not overflow, will remain as it is.
Fixed
Fixed
Fixed
(-) The context of the method vote() needs more than the returns values of votingCost(). It will not be changed for the lower gas to call.
(?) Type struct Project is only valid in storage because it contains a mapping.