这是作业:
修改第4章中的迷宫问题,使其可以从用户定义的起始位置(0,0除外)开始,并搜索用户定义的终点。
整个程序似乎看起来很好,我仍然要弄乱用户输入的部分,但有一行有错误,我不知道如何摆脱它。任何帮助将不胜感激。
有错误的行是: StackADT stack = new LinkedStackADT(); 它告诉我LinkedStackADT无法解析为某种类型。
另外,如何让迷宫接受用户定义的起始位置和结束点?感谢您提供任何可能的帮助!
public class Maze
{
public interface StackADT<T> {
public void push (T element);
public T pop();
public T peek();
public boolean isEmpty();
public int size();
public String toString();
}
public static void main(String[] args){
abstract class LinkedStack<T> implements StackADT<T>
{
private int count;
private LinearNode<T> top;
public LinkedStack()
{
count = 0;
top = null;
}
class LinearNode<T>
{
private LinearNode<T> next;
private T element;
public LinearNode()
{
next = null;
element = null;
}
public LinearNode(T elem)
{
next = null;
element = elem;
}
public LinearNode<T> getNext()
{
return next;
}
public void setNext(LinearNode<T> node)
{
next = node;
}
public T getElement()
{
return element;
}
public void setElement(T elem)
{
element = elem;
}
}
class Position
{
private int x;
private int y;
Position ()
{
x = 0;
y = 0;
}
public int getx()
{
return x;
}
public int gety()
{
return y;
}
public void setx1(int a)
{
x = a;
}
public void sety(int a)
{
y = a;
}
public void setx(int x2) {
}
}
private final int TRIED = 3;
private final int PATH = 7;
private int [][] grid = {{1,1,1,0,1,1,0,0,0,1,1,1,1},
{1,0,0,1,1,0,1,1,1,1,0,0,1},
{1,1,1,1,1,0,1,0,1,0,1,0,0},
{0,0,0,0,1,1,1,0,1,0,1,1,1},
{1,1,1,0,1,1,1,0,1,0,1,1,1},
{1,0,1,0,0,0,0,1,1,1,0,0,1},
{1,0,1,1,1,1,1,1,0,1,1,1,1},
{1,0,0,0,0,0,0,0,0,0,0,0,0},
{1,1,1,1,1,1,1,1,1,1,1,1,1}};
public StackADT<Position> push_new_pos(int x, int y,
StackADT<Position> stack)
{
Position npos = new Position();
npos.setx1(x);
npos.sety(y);
if (valid(npos.getx(),npos.gety()))
stack.push(npos);
return stack;
}
public boolean traverse ()
{
boolean done = false;
Position pos = new Position();
Object dispose;
StackADT<Position> stack = new LinkedStackADT<Position> ();
stack.push(pos);
while (!(done))
{
pos = stack.pop();
grid[pos.getx()][pos.gety()] = TRIED; // this cell has been tried
if (pos.getx() == grid.length-1 && pos.gety() == grid[0].length-1)
done = true; // the maze is solved
else
{
stack = push_new_pos(pos.getx(),pos.gety() - 1, stack);
stack = push_new_pos(pos.getx(),pos.gety() + 1, stack);
stack = push_new_pos(pos.getx() - 1,pos.gety(), stack);
stack = push_new_pos(pos.getx() + 1,pos.gety(), stack);
}
}
return done;
}
private boolean valid (int row, int column)
{
boolean result = false;
if (row >= 0 && row < grid.length &&
column >= 0 && column < grid[row].length)
if (grid[row][column] == 1)
result = true;
return result;
}
public String toString ()
{
String result = "\n";
for (int row=0; row < grid.length; row++)
{
for (int column=0; column < grid[row].length; column++)
result += grid[row][column] + "";
result += "\n";
}
return result;
}
}
}
}
答案 0 :(得分:0)
您没有定义为LinkedStack
的类型(或类)。您的类型为new
,但它是抽象的,因此 abstract
会失败。如果从LinkedStack
中删除bool
关键字,则应该是可实例化的。 (注意:instantiatable不是真正的单词)