package question;

/*
 @author: Roderland
 @create: 2020年09月19日---23:17
*/
public class Question980 {

 private int[][] grid;
 private int pathCount;
 private int count;

 public int uniquePathsIII(int[][] grid) {
 this.grid = grid;
 pathCount = 0;
 int x = 0;
 int y = 0;
 for (int i = 0; i < grid.length; i++) {
 for (int j = 0; j < grid[i].length; j++) {
 if (grid[i][j] == 0) pathCount++;
 if (grid[i][j] == 1) {
 x = i;
 y = j;
 }
 }
 }
 fun(x, y);
 return count;
 }

 public void fun(int i, int j) {
 if (j + 1 < grid[i].length) partOfFun(i, j + 1);
 if (i + 1 < grid.length) partOfFun(i + 1, j);
 if (j - 1 >= 0) partOfFun(i, j - 1);
 if (i - 1 >= 0) partOfFun(i - 1, j);
 }

 private void partOfFun(int i, int j) {
 if (grid[i][j] == 0) {
 pathCount--;
 grid[i][j] = 1;
 fun(i, j);
 grid[i][j] = 0;
 pathCount++;
 } else if (grid[i][j] == 2 && pathCount == 0) count++;
 }

}