View Compilation Error

0_0_9753887_31316.cpp: In function `void haha(char*, char*)':
0_0_9753887_31316.cpp:16: error: `printf' undeclared (first use this function)
0_0_9753887_31316.cpp:16: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_9753887_31316.cpp: In function `int main()':
0_0_9753887_31316.cpp:28: error: `scanf' undeclared (first use this function)