川渡りパズル c言語

川渡り問題が課題で出され、16行目と40行目を書いたのですが、思っていた実行結果が出ません。
おそらく40行目が違うと思うのですがどうすればいいかわかりません。
よろしくお願いします。

c
1#include <stdio.h>
2#include <string.h>
3
4#define  NODES  16
5#define  LEFT  0
6#define  RIGHT  1
7
8struct NODE {
9  int Farmer, Wolf, Capra, Cabbage;
10} node[NODES];
11
12int number_of_answers = 0;
13
14int inhibit(int step)
15{
16  return( (node[step].Farmer != node[step].Capra) && ((node[step].Farmer != node[step].Wolf) ||
17		  (node[step].Farmer != node[step].Cabbage)) );
18}
19
20int previous(int step)
21{
22  int Farmer, Wolf, Capra, Cabbage, i;
23
24  Farmer = node[step].Farmer;
25  Wolf = node[step].Wolf;
26  Capra = node[step].Capra;
27  Cabbage = node[step].Cabbage;
28
29  for (i=0; i<step; i++) {
30    if ( (Farmer == node[i].Farmer) && (Wolf == node[i].Wolf) &&
31	 (Capra == node[i].Capra)  && (Cabbage == node[i].Cabbage) ) {
32      return 1;
33    }
34  }
35  return 0;
36}
37
38int final_state(int step)
39{
40  return (node[step].Farmer = node[step].Capra = node[step].Wolf = node[step].Cabbage = RIGHT);
41}
42
43void print_member(int step, int lr)
44{
45  printf("[");
46  if (node[step].Farmer == lr)  printf("Farmer "); else printf("       ");
47  if (node[step].Wolf == lr)    printf("Wolf   "); else printf("       ");
48  if (node[step].Capra == lr)   printf("Capra  "); else printf("       ");
49  if (node[step].Cabbage == lr) printf("Cabbage"); else printf("       ");
50  printf("]");
51}
52
53void print_answer(int step)
54{
55  int i;
56
57  printf("*** Answer #%d ***\n", ++number_of_answers);
58
59  for (i=0; i<=step; i++) {
60    printf("%5d.  ", i+1);
61    print_member(i, LEFT);
62
63    if (i == step) {
64      printf("  ====  ");
65    }
66    else {
67      if (node[i].Farmer == LEFT)  {
68	printf("  ===>  ");
69      }
70      else {
71	printf("  <===  ");
72      }
73    }
74
75    print_member(i, RIGHT);
76    printf("\n");
77  }
78  printf("\n");
79}
80
81void search(int step)
82{
83  int next;
84  int Farmer;
85
86  if (final_state(step)) {
87    print_answer(step);
88    return;
89  }
90
91  if (inhibit(step) || previous(step)) return;
92
93  next = step + 1;
94  Farmer = node[step].Farmer;
95
96  node[next].Farmer = 1 - Farmer;
97  node[next].Wolf = node[step].Wolf;
98  node[next].Capra = node[step].Capra;
99  node[next].Cabbage = node[step].Cabbage;
100  search(next);
101
102  if (node[step].Wolf == Farmer) {
103    node[next].Wolf = 1-Farmer;
104    search(next);
105    node[next].Wolf = Farmer;
106  }
107
108  if (node[step].Capra == Farmer) {
109    node[next].Capra = 1-Farmer;
110    search(next);
111    node[next].Capra = Farmer;
112  }
113
114  if (node[step].Cabbage == Farmer) {
115    node[next].Cabbage = 1-Farmer;
116    search(next);
117    node[next].Cabbage = Farmer;
118  }
119}
120
121int main(void)
122{
123  node[0].Farmer = node[0].Wolf = node[0].Capra = node[0].Cabbage = LEFT;
124
125  search(0);
126
127  return 0;
128}
129
130

行動規範の内容に同意します

回答1件

ベストアンサー

C
1int final_state(int step)
2{
3  if(node[step].Farmer == LEFT)
4    return 0;
5    
6  if(node[step].Capra == LEFT)
7    return 0;
8    
9  if(node[step].Wolf == LEFT)
10    return 0;
11    
12  if(node[step].Cabbage == LEFT)
13    return 0;
14    
15  return 1;
16}