View Compilation Error

372511_0_0_21358.cpp: In function `int main()':
372511_0_0_21358.cpp:4: error: `b' undeclared (first use this function)
372511_0_0_21358.cpp:4: error: (Each undeclared identifier is reported only once for each function it appears in.)
372511_0_0_21358.cpp:4: error: `scanf' undeclared (first use this function)
372511_0_0_21358.cpp:4: error: `EOF' undeclared (first use this function)
372511_0_0_21358.cpp:6: error: `printf' undeclared (first use this function)