0_0_38593260_18631.cpp 0_0_38593260_18631.cpp(5) : error C2065: “a”: 未声明的标识符 0_0_38593260_18631.cpp(5) : error C2065: “b”: 未声明的标识符 0_0_38593260_18631.cpp(6) : error C2065: “a”: 未声明的标识符 0_0_38593260_18631.cpp(6) : error C2065: “b”: 未声明的标识符