View Compilation Error

0_0_29469571_25757.cpp:3:12: error: #include expects "FILENAME" or <FILENAME>
 #include   
            ^
0_0_29469571_25757.cpp: In function 'int main()':
0_0_29469571_25757.cpp:13:24: error: 'scanf' was not declared in this scope
  while (~scanf("%d", &t))
                        ^
0_0_29469571_25757.cpp:49:17: error: 'printf' was not declared in this scope
    printf("-1\n");
                 ^
0_0_29469571_25757.cpp:55:32: error: 'printf' was not declared in this scope
   printf("%.2lf\n", sum2 / sum1);
                                ^