0_0_38899434_14476.cpp 0_0_38899434_14476.cpp(11) : error C2065: “cin”: 未声明的标识符 0_0_38899434_14476.cpp(15) : error C2065: “cout”: 未声明的标识符 0_0_38899434_14476.cpp(15) : error C2065: “endl”: 未声明的标识符