View Compilation Error

0_0_35244639_904.cpp: In function 'int main()':
0_0_35244639_904.cpp:12:25: error: 'scanf' was not declared in this scope
     while(~scanf("%d",&n))
                         ^
0_0_35244639_904.cpp:14:29: error: 'printf' was not declared in this scope
         printf("%lld\n",a[n]);
                             ^