View Compilation Error

0_0_4940243_26445.cpp: In function `int main()':
0_0_4940243_26445.cpp:11: error: `scanf' undeclared (first use this function)
0_0_4940243_26445.cpp:11: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_4940243_26445.cpp:12: error: `memset' undeclared (first use this function)
0_0_4940243_26445.cpp:29: error: `cout' undeclared (first use this function)
0_0_4940243_26445.cpp:29: error: `endl' undeclared (first use this function)