View Compilation Error

0_0_35213766_22516.cpp: In function 'bool eq(double, double)':
0_0_35213766_22516.cpp:17:18: error: 'fabs' was not declared in this scope
   return fabs(a-b) < 1e-9;
                  ^
0_0_35213766_22516.cpp: In function 'int main()':
0_0_35213766_22516.cpp:88:34: error: 'lround' was not declared in this scope
         printf("%ld\n",lround(ans));
                                  ^