View Compilation Error

0_0_37210294_13040.cpp: In function 'int main()':
0_0_37210294_13040.cpp:7:22: error: 'scanf' was not declared in this scope
  while(~scanf("%d",&n))
                      ^
0_0_37210294_13040.cpp:12:18: error: 'printf' was not declared in this scope
   printf("%lld",t);
                  ^