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0_0_39738351_4844.cpp
0_0_39738351_4844.cpp(25) : error C3867: “std::basic_string<char,std::char_traits<char>,std::allocator<char>>::length”:  函数调用缺少参数列表；请使用“&std::basic_string<char,std::char_traits<char>,std::allocator<char>>::length”创建指向成员的指针
0_0_39738351_4844.cpp(25) : error C2296: “-”: 非法，左操作数包含“unsigned int (__thiscall std::basic_string<char,std::char_traits<char>,std::allocator<char>>::* )(void) throw() const”类型
0_0_39738351_4844.cpp(31) : error C2065: “l”: 未声明的标识符
0_0_39738351_4844.cpp(32) : error C2065: “l”: 未声明的标识符