Some cstdlib function prototypes
- double atof(const char n[]) -- converts the c-style string n to a double
- int atoi(const char n[]) -- converts the c-style string n to an int
- long atol(const char n[]) -- converts the c-style string n to a long
- int rand() -- returns a pseudo random number in the range 0..RAND_MAX inclusive.
- void srand(unsigned int seed) -- uses the argument seed to start a pseudo random number sequence
- int abs(int j) -- absolute value of j
- long labs(long j) -- absolute value of j