1 #include "fe.h" 2 3 /* 4 return 1 if f is in {1,3,5,...,q-2} 5 return 0 if f is in {0,2,4,...,q-1} 6 7 Preconditions: 8 |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc. 9 */ 10 fe_isnegative(const fe f)11int fe_isnegative(const fe f) 12 { 13 unsigned char s[32]; 14 fe_tobytes(s,f); 15 return s[0] & 1; 16 } 17