/in/foo.cc: In function 'int main()':
/in/foo.cc:30:27: error: 'scanf' was not declared in this scope
     scanf("%d%d", &n1, &n2);
                           ^
/in/foo.cc:45:35: error: 'printf' was not declared in this scope
     printf("%d %d", countA, countB);
                                   ^