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81 lines
2.1 KiB
C
81 lines
2.1 KiB
C
/* j/4/in_mer.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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u3qdi_mer(u3_noun a,
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u3_noun b)
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{
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if ( u3_nul == a ) {
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return u3k(b);
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}
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else if ( u3_nul == b ) {
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return u3k(a);
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}
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else {
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u3_noun l_a, n_a, r_a, lr_a; // XX copy tree boilerplate to other pt4
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u3_noun l_b, n_b, r_b, lr_b;
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u3_noun c;
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if ( (c3n == u3r_cell(a, &n_a, &lr_a)) ) {
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return u3m_bail(c3__exit);
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}
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else if ( (c3n == u3r_cell(b, &n_b, &lr_b)) ) {
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return u3m_bail(c3__exit);
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}
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else {
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if ( c3y == u3qc_mor(n_b, n_a) ) {
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c = a; a = b; b = c;
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c = n_a; n_a = n_b; n_b = c;
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c = lr_a; lr_a = lr_b; lr_b = c;
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}
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if ( c3n == u3r_cell(lr_a, &l_a, &r_a) ) {
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return u3m_bail(c3__exit);
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}
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else if ( c3n == u3r_cell(lr_b, &l_b, &r_b) ) {
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return u3m_bail(c3__exit);
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}
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else if ( c3y == u3r_sing(n_a, n_b) ) {
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return u3nt(u3k(n_a),
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u3qdi_mer(l_a, l_b),
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u3qdi_mer(r_a, r_b));
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}
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else if ( c3y == u3qc_gor(n_b, n_a) ) {
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return u3qdi_mer(u3nt(n_a,
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u3qdi_mer(l_a,
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u3nt(n_b,
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l_b,
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u3_nul)),
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r_a),
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r_b);
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}
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else {
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return u3qdi_mer(u3nt(n_a,
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l_a,
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u3qdi_mer(r_a,
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u3nt(n_b,
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u3_nul,
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r_b))),
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l_b);
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}
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}
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}
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}
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u3_noun
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u3wdi_mer(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, &b, u3x_con_sam, &a, 0) ) {
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return u3m_bail(c3__exit);
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}
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else {
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return u3qdi_mer(a, b);
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}
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}
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