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47 lines
685 B
C
47 lines
685 B
C
/* j/3/peg.c
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**
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*/
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#include "all.h"
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/* functions
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*/
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u3_noun
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u3qc_peg(u3_atom a,
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u3_atom b)
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{
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u3_atom c, d, e, f, g, h;
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c = u3r_met(0, b);
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d = u3qa_dec(c);
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e = u3qc_lsh(0, d, 1);
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f = u3qa_sub(b, e);
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g = u3qc_lsh(0, d, a);
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h = u3qa_add(f, g);
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u3z(c);
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u3z(d);
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u3z(e);
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u3z(f);
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u3z(g);
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return h;
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}
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u3_noun
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u3wc_peg(u3_noun cor)
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{
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u3_noun a, b;
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if ( (c3n == u3r_mean(cor, u3x_sam_2, &a, u3x_sam_3, &b, 0)) ||
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(c3n == u3ud(a)) ||
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(c3n == u3ud(b)) ||
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(0 == a) ||
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(0 == b) )
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{
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return u3m_bail(c3__exit);
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} else {
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return u3qc_peg(a, b);
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}
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}
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