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89 lines
2.8 KiB
C
89 lines
2.8 KiB
C
/* j/4/in_mer.c
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**
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** This file is in the public domain.
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*/
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#include "all.h"
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/* functions
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*/
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u2_noun
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u2_cqdi_mer(u2_noun a, u2_noun b)
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{
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if ( u2_nul == a ) {
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return u2k(b);
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}
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else if ( u2_nul == b ) {
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return u2k(a);
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}
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else {
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u2_noun l_a, n_a, r_a, lr_a; // XX copy tree boilerplate to other pt4
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u2_noun l_b, n_b, r_b, lr_b;
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u2_noun c;
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if ( (u2_no == u2_cr_cell(a, &n_a, &lr_a)) ) {
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return u2_cm_bail(c3__exit);
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}
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else if ( (u2_no == u2_cr_cell(b, &n_b, &lr_b)) ) {
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return u2_cm_bail(c3__exit);
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}
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else {
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if ( u2_yes == u2_cqc_vor(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 ( u2_no == u2_cr_cell(lr_a, &l_a, &r_a) ) {
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return u2_cm_bail(c3__exit);
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}
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else if ( u2_no == u2_cr_cell(lr_b, &l_b, &r_b) ) {
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return u2_cm_bail(c3__exit);
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}
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else if ( u2_yes == u2_cr_sing(n_a, n_b) ) {
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return u2nt(u2k(n_a),
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u2_cqdi_mer(l_a, l_b),
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u2_cqdi_mer(r_a, r_b));
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}
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else if ( u2_yes == u2_cqc_hor(n_b, n_a) ) {
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return u2_cqdi_mer(
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u2nt(
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n_a,
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u2_cqdi_mer(
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l_a,
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u2nt(
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n_b,
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l_b,
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u2_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 u2_cqdi_mer(
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u2nt(
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n_a,
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l_a,
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u2_cqdi_mer(
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r_a,
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u2nt(
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n_b,
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u2_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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u2_noun
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u2_cwdi_mer(u2_noun cor)
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{
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u2_noun a, b;
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if ( u2_no == u2_cr_mean(cor, u2_cv_sam, &b, u2_cv_con_sam, &a, 0) ) {
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return u2_cm_bail(c3__exit);
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}
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else {
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return u2_cqdi_mer(a, b);
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}
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}
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