用深搜写的
用哈系表判重
如果有时间帮我看看好吗  我在zju上也交过无数次了 再不行只能放弃了……
谢了

#include <stdio.h>
#include <stdlib.h>

const
  int maxn = 30000;
  int cmax [9][9] = {0, 1, 2, 1, 2, 3, 2, 3, 4,
		 1, 0, 1, 2, 1, 2, 3, 2, 3,
		 2, 1, 0, 3, 2, 1, 4, 3, 2,
		 1, 2, 3, 0, 1, 2, 1, 2, 3,
		 2, 1, 2, 1, 0, 1, 2, 1, 2,
		 3, 2, 1, 2, 1, 0, 3, 2, 1,
		 2, 3, 4, 1, 2, 3, 0, 1, 2,
		 3, 2, 3, 2, 1, 2, 1, 0, 1,
		 4, 3, 2, 3, 2, 1, 2, 1, 0};

struct point
{
  int value, step;
  point *next;
};

point * hx[maxn], * p, *ne, *te;

int result, i, j, k, l, n, pos, max, path[100], opath[100], num, ten[10] = {1,100000000, 10000000, 1000000, 100000, 10000, 1000, 100, 10, 1};
char c;

void search(int deep)
{
  if (num == 123456780)
  {
    max = deep;
    for (i = 0; i < deep; i ++)
      opath[i] = path[i];
    return;
  }
  if (deep + 1 >= max) return;
  int last, lpos;

  last = num; lpos = pos;

  i = num % maxn;
  p = hx[i];
  while (p->next != NULL)
  {
    if (p->next->value == num)
    {
      if (p->next->step <= deep) return;
	else {(p->next->step = deep);break;}
    } else
    if (p->next->value < num) break;
    p = p->next;

  }
  if (p->next == NULL)
  {
    ne = new(struct point);
    ne-> next = p->next;
    p -> next = ne;
    ne-> value = num;
    ne-> step = deep;
  } else
  if (p->next->value < num)
  {
    ne = new(struct point);
    ne-> next = p->next;
    p -> next = ne;
    ne-> value = num;
    ne-> step = deep;
  }


//d
  if (pos < 7)
  {
    i = num / ten[pos] % 10;
    j = num / ten[pos + 3] % 10;
    num = num - i * ten[pos] - j * ten[pos + 3] + j * ten[pos] + i * ten[pos + 3];
    pos = pos + 3;

    path[deep] = 4;
    search(deep + 1);
  }
//u
  pos = lpos;num = last;
  if (pos > 3)
  {
    i = num / ten[pos] % 10;
    j = num / ten[pos - 3] % 10;
    num = num - i * ten[pos] - j * ten[pos - 3] + j * ten[pos] + i * ten[pos - 3];
    pos = pos - 3;

    path[deep] = 1;
    search(deep + 1);
  }
//r
  pos = lpos;num = last;
  if (pos % 3 != 0)
  {
    i = num / ten[pos] % 10;
    j = num / ten[pos + 1] % 10;
    num = num - i * ten[pos] - j * ten[pos + 1] + j * ten[pos] + i * ten[pos + 1];
    pos = pos + 1;

    path[deep] = 2;
    search(deep + 1);
  }
//l
  pos = lpos;num = last;
  if (pos % 3 != 1)
  {
    i = num / ten[pos] % 10;
    j = num / ten[pos - 1] % 10;
    num = num - i * ten[pos] - j * ten[pos - 1] + j * ten[pos] + i * ten[pos - 1];
    pos = pos - 1;

    path[deep] = 3;
    search(deep + 1);
  }
}

main()
{
  num = 0; max = 0;
  for (i = 1; i <= 9; i ++)
  {
    scanf("%c", &c);
    if (i != 9) scanf(" ");
    if (c == 'x') {num = num * 10; pos = i;}else
    {
      num = num * 10 + c - 48;
      max = max + cmax[i][c - 48];
    }
  }
  for (i = 0; i < maxn; i ++)
  {
    hx[i] = new(struct point);
    hx[i]->next = NULL;
  }

  max = max + 30;
  result = max;
  search(0);
  if (result == max) printf("unsolvable"); else
  for (i = 0; i < max; i ++)
    if (opath[i] == 1) printf("u"); else
    if (opath[i] == 2) printf("r"); else
    if (opath[i] == 3) printf("l"); else
    if (opath[i] == 4) printf("d"); else
  for (i = 0; i < maxn; i ++)
  {
    p = hx[i];
    while (p != NULL)
    {
      ne = p->next;
      free(p);
      p = ne;
    }
  }
  printf("\n");
}

• 帮你看代码是不可能的，只能定位一下re的错误位置 (3785) hawk 2004-07-17 12:46:58