View Compilation Error

0_0_12181435_11088.cpp: In function `int main()':
0_0_12181435_11088.cpp:76: error: `fabs' undeclared (first use this function)
0_0_12181435_11088.cpp:76: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_12181435_11088.cpp:86: error: `sqrt' undeclared (first use this function)