658156_0_0_6485.cpp 658156_0_0_6485.cpp(10) : error C2065: “whilecin” : 未声明的标识符 658156_0_0_6485.cpp(11) : error C2065: “a” : 未声明的标识符 658156_0_0_6485.cpp(11) : error C2143: 语法错误 : 缺少“;”(在“{”的前面)