17 lines
266 B
C
17 lines
266 B
C
#include "fe.h"
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/*
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return 1 if f is in {1,3,5,...,q-2}
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return 0 if f is in {0,2,4,...,q-1}
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Preconditions:
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|f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
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*/
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int fe_isnegative(const fe f)
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{
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unsigned char s[32];
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fe_tobytes(s,f);
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return s[0] & 1;
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}
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