View Compilation Error

0_0_32001682_18767.cpp: In function 'double f(double, double, double, double)':
0_0_32001682_18767.cpp:6:28: error: 'pow' was not declared in this scope
     return sqrt(pow(x2-x1,2)+pow(y2-y1,2));
                            ^
0_0_32001682_18767.cpp:6:42: error: 'sqrt' was not declared in this scope
     return sqrt(pow(x2-x1,2)+pow(y2-y1,2));
                                          ^