#include <stdio.h>
#define ROWS 5
#define COLS 5

int main ()
{
  int n, r, c, space = ROWS*COLS - 1;
  int grid[ROWS*COLS];
  char move;

  for ( n = 0; n < ROWS*COLS; ++n )
      grid[n] = ROWS*COLS - 1 - n;

  do {
    for ( r = 0; r < ROWS; ++r ) {
      for ( c = 0; c < COLS; ++c )
        if ( grid[r * COLS + c] == 0 ) printf("   ");
        else printf("%3d", grid[r * COLS + c]);
      printf("\n");
    }

    printf("Enter Space Movement (U: Up, D: Down, R: Right, L: Left, E: Exit): ");
    scanf(" %c", &move);

    switch(move) {
      case 'U':
      case 'u':
        if ( space - COLS >= 0 ) {
          grid[space] = grid[space - COLS];
          grid[space - COLS] = 0;
          space = space - COLS;
        }
        break;

      case 'D':
      case 'd':
        if ( space + COLS < ROWS*COLS ) {
          grid[space] = grid[space + COLS];
          grid[space + COLS] = 0;
          space = space + COLS;
        }
        break;

      case 'R':
      case 'r':
        if ( (space+1)%COLS != 0 ) {
          grid[space] = grid[space + 1];
          grid[space + 1] = 0;
          space = space + 1;
        }
        break;

      case 'L':
      case 'l':
        if ( space%COLS != 0 ) {
          grid[space] = grid[space - 1];
          grid[space - 1] = 0;
          space = space - 1;
        }
        break;

      case 'E':
      case 'e':
        break;

      default:
        printf("-- Choice NOT Listed --\n");
        break;
    }
  } while ( (move != 'E') && (move != 'e') );  

  return 0;
}