View Compilation Error

0_0_4876000_20457.cpp:3: error: `main' must return `int'
0_0_4876000_20457.cpp: In function `int main(...)':
0_0_4876000_20457.cpp:6: error: `scanf' undeclared (first use this function)
0_0_4876000_20457.cpp:6: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_4876000_20457.cpp:6: error: `EOF' undeclared (first use this function)
0_0_4876000_20457.cpp:19: error: `printf' undeclared (first use this function)