View Compilation Error

0_0_9857957_1562.cpp:3:18: cmath.h: No such file or directory
0_0_9857957_1562.cpp: In function `int main()':
0_0_9857957_1562.cpp:8: error: `sqrt' undeclared (first use this function)
0_0_9857957_1562.cpp:8: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_9857957_1562.cpp:13: error: `N' undeclared (first use this function)