View Compilation Error

0_0_7627998_28449.cpp: In function `double Distance(int, int)':
0_0_7627998_28449.cpp:20: error: `sqrt' undeclared (first use this function)
0_0_7627998_28449.cpp:20: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_7627998_28449.cpp: In function `double Divide(int, int)':
0_0_7627998_28449.cpp:44: error: `fabs' undeclared (first use this function)