View Compilation Error

0_0_35028431_18113.cpp: In function 'int main()':
0_0_35028431_18113.cpp:4:21: error: 'scanf' was not declared in this scope
  for (scanf("%d", &n); n; n--)
                     ^
0_0_35028431_18113.cpp:12:46: error: 'printf' was not declared in this scope
   printf("%d%s", zong, n == 1 ? "\n" : "\n\n");
                                              ^