View Compilation Error

0_0_19217571_6641.cpp: In function 'int main(int, char**)':
0_0_19217571_6641.cpp:8:22: error: 'scanf' was not declared in this scope
  while(scanf("%ld",&n) && n)
                      ^
0_0_19217571_6641.cpp:21:22: error: 'printf' was not declared in this scope
   printf("%d\n",count);
                      ^