View Compilation Error

197037_0_2786.cpp: In function `int main()':
197037_0_2786.cpp:6: error: no match for 'operator>' in 'std::cin > (a >> b)'
197037_0_2786.cpp:14: error: `f0' undeclared (first use this function)
197037_0_2786.cpp:14: error: (Each undeclared identifier is reported only once for each function it appears in.)