View Compilation Error

0_0_36092597_13127.cpp:1:9: error: #include expects "FILENAME" or <FILENAME>
 #include
         ^
0_0_36092597_13127.cpp: In function 'int main()':
0_0_36092597_13127.cpp:7:34: error: 'scanf' was not declared in this scope
         while(scanf("%[^\n]%*c",a)!=EOF)
                                  ^
0_0_36092597_13127.cpp:7:37: error: 'EOF' was not declared in this scope
         while(scanf("%[^\n]%*c",a)!=EOF)
                                     ^
0_0_36092597_13127.cpp:26:46: error: 'printf' was not declared in this scope
                         printf("%.2f\n",sum/i);
                                              ^
0_0_36092597_13127.cpp:28:65: error: 'printf' was not declared in this scope
                         printf("Unknown letter grade in input\n");
                                                                 ^