View Compilation Error

0_0_36108587_3156.cpp: In function 'int main()':
0_0_36108587_3156.cpp:39:19: error: 'scanf' was not declared in this scope
     scanf("%d", &T);
                   ^
0_0_36108587_3156.cpp:42:62: error: 'printf' was not declared in this scope
         printf("Case #%d: %lld\n", cas, fuck(r) - fuck(l - 1));
                                                              ^