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45 lines
905 B
C
45 lines
905 B
C
/* j/2/skid.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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u3qb_skid(u3_noun a,
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u3_noun b)
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{
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if ( 0 == a ) {
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return u3nc(u3_nul, u3_nul);
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}
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else if ( c3n == u3du(a) ) {
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return u3m_bail(c3__exit);
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} else {
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u3_noun acc = u3qb_skid(u3t(a), b);
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u3_noun hoz = u3n_slam_on(u3k(b), u3k(u3h(a)));
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switch ( hoz ) {
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case c3y: acc = u3nc(u3nc(u3k(u3h(a)), u3h(acc)), u3t(acc));
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break;
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case c3n: acc = u3nc(u3h(acc), u3nc(u3k(u3h(a)), u3t(acc)));
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break;
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default: u3z(hoz);
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return u3m_bail(c3__exit);
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}
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u3z(hoz);
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return acc;
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}
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}
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u3_noun
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u3wb_skid(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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return u3m_bail(c3__exit);
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} else {
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return u3qb_skid(a, b);
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}
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}
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