1 条题解

  • 0
    @ 2022-7-9 15:54:39

    该比赛官方题解,如要AC,请将文件输入输出改为stdio。

    /* Contest   : Ulm Local Contest 1997 
     * Problem D : Dungeon Master
     * Method    : Breadth-First Search
     * Author    : Mark Dettinger
     * Date      : May 29, 1997
     */
    
    #include <stdio.h>
    #include <assert.h>
    
    #define WHITE 0
    #define GRAY 1
    #define BLACK 2
    #define oo 1000000000
    
    typedef struct { int lev,row,col; } cell;
    
    FILE *input;
    
    int rows,cols,levels;
    char dungeon[40][40][40];
    int d[40][40][40],color[40][40][40];
    cell queue[30000];
    int head,tail;
    
    void skip_line() { while (fgetc(input)!='\n'); }
    
    void enqueue (int l, int i, int j)
    {
      queue[tail].lev = l;
      queue[tail].row = i;
      queue[tail].col = j;
      tail++;
      color[l][i][j] = GRAY;
    }
    
    void dequeue (int *l, int *i, int *j)
    {
      *l = queue[head].lev;
      *i = queue[head].row;
      *j = queue[head].col;
      head++;
      color[*l][*i][*j] = BLACK;
    }
    
    void visit (int level, int row, int col, int distance)
    {
      if (level<0 || level>=levels || row<0 || row>=rows || col<0 || col>=cols || 
          dungeon[level][row][col]=='#' || color[level][row][col]!=WHITE) return;
      d[level][row][col] = distance;
      enqueue(level,row,col);
    }
    
    int read_case()
    {
      int l,i;
    
      fscanf(input,"%d %d %d",&levels,&rows,&cols);
      if (levels==0 && rows==0 && cols==0) return 0;
      skip_line();
      for (l=0; l<levels; l++)
        for (i=0; i<=rows; i++)
          fgets(dungeon[l][i],40,input);
      return 1;
    }
    
    void solve_case()
    {
      cell start;
      int l,i,j,newd;
      
      /* 1. Initialization */
    
      for (l=0; l<levels; l++)
        for (i=0; i<rows; i++)
          for (j=0; j<cols; j++)
    	{
    	  color[l][i][j] = WHITE;
    	  d[l][i][j] = oo;
    	  if (dungeon[l][i][j]=='S')
    	    { start.lev = l; start.row = i; start.col = j; }
    	}
    
      /* 2. Breadth-First Search */
    
      head = tail = 0;
      visit(start.lev,start.row,start.col,0);
      while (head!=tail)
        {
          dequeue(&l,&i,&j);
          if (dungeon[l][i][j]=='E') break;
          newd = d[l][i][j]+1;
          visit(l  , i-1, j  , newd);  /* North */
          visit(l  , i+1, j  , newd);  /* South */
          visit(l  , i  , j+1, newd);  /* East  */
          visit(l  , i  , j-1, newd);  /* West  */
          visit(l+1, i  , j  , newd);  /* Up    */
          visit(l-1, i  , j  , newd);  /* Down  */
        }
    
      /* 3. Output */
    
      if (dungeon[l][i][j]=='E')
        printf("Escaped in %d minute(s).\n",d[l][i][j]);
      else
        printf("Trapped!\n");
    }
    
    int main()
    {
      input = fopen("dungeon.in","r");
      assert(input!=NULL);
      while (read_case()) solve_case();
      fclose(input);
      return 0;
    }
    
    • 1

    信息

    ID
    1828
    时间
    1000ms
    内存
    256MiB
    难度
    8
    标签
    递交数
    63
    已通过
    12
    上传者