src.cpp: In function 'int main()':
src.cpp:8:2: error: 'cin' was not declared in this scope
cin >> a >> b >> c;
^
src.cpp:14:2: error: 'cout' was not declared in this scope
cout << setiosflags(ios::fixed) << setprecision(2);
^
src.cpp:14:22: error: incomplete type 'std::ios {aka std::basic_ios<char>}' used in nested name specifier
cout << setiosflags(ios::fixed) << setprecision(2);
^