View Compilation Error

0_0_21994095_15866.cpp: In function 'int main()':
0_0_21994095_15866.cpp:34:23: error: 'scanf' was not declared in this scope
  int T; scanf("%d", &T);
                       ^
0_0_21994095_15866.cpp:46:23: error: 'printf' was not declared in this scope
   printf("%lld\n", ans);
                       ^