1 #include <u.h> 2 #include <libc.h> 3 4 int abs(int a)5 abs(int a) 6 { 7 if(a < 0) 8 return -a; 9 return a; 10 } 11 12 long labs(long a)13 labs(long a) 14 { 15 if(a < 0) 16 return -a; 17 return a; 18 } 19