View Compilation Error

0_0_19114496_31307.cpp:1:10: error: #include expects "FILENAME" or <FILENAME>
 #include 
          ^
0_0_19114496_31307.cpp: In function 'int main()':
0_0_19114496_31307.cpp:5:27: error: 'scanf' was not declared in this scope
 while(scanf("%d%d", &a, &b) != EOF)
                           ^
0_0_19114496_31307.cpp:5:32: error: 'EOF' was not declared in this scope
 while(scanf("%d%d", &a, &b) != EOF)
                                ^
0_0_19114496_31307.cpp:14:15: error: 'printf' was not declared in this scope
 printf("%d", n); //尾数为0,1,5,6 时, a^b以后还是一样的 
               ^
0_0_19114496_31307.cpp:49:12: error: 'printf' was not declared in this scope
 printf("\n");
            ^