cadouri.cpp:32: error: expected constructor, destructor, or type conversion before 'using' cadouri.cpp:33: error: redefinition of 'std::ifstream fin' cadouri.cpp:4: error: 'std::ifstream fin' previously declared here cadouri.cpp:34: error: redefinition of 'std::ofstream fout' cadouri.cpp:5: error: 'std::ofstream fout' previously declared here cadouri.cpp:35: error: redefinition of 'int n' cadouri.cpp:6: error: 'int n' previously declared here cadouri.cpp: In function 'int main()': cadouri.cpp:36: error: redefinition of 'int main()' cadouri.cpp:7: error: 'int main()' previously defined here