Range of motion of the robot-sword

Description of the robot's motion range topic

There is a M-row and N-column squares on the ground. A robot moves from the grid of coordinates 0,0, each time only to the left, right, upper and lower four directions, but cannot enter the coordinates of the row and column coordinates of the sum of the squares greater than K. For example, when K is 18 o'clock, the robot can enter the square (35,37) because 3+5+3+7 = 18. However, it cannot enter the grid (35,38) because 3+5+3+8 = 19. How many grids can the robot reach?

Ideas

1. This is similar to the "path in the Matrix" topic, all using backtracking, but the starting point of this question is fixed, that is, starting from the (0,0) position.
2. We also create a matrix based on the number of rows and columns, and this matrix is a matrix of packet wildest, where each location stores the number of each bit in the position subscript, and then the direct comparison can be
3. This topic is about the maximum number of squares that can be reached, so we don't have to reduce the result by 1 when we're on the stack, because if we go through, we can get there.

Code

Import Java.util.Stack;PublicClass Solution {PublicIntMovingcount(int threshold,int rows,int cols) {int result =0;if (Threshold <=0 | | Rows <=0 | | Cols <=0) {return result; }int[][] data =NewInt[rows +2][cols +2];for (int i =0; I < rows +2; i++) {for (Int J =0; J < cols +2; J + +) {if (i = =0 | | i = = (rows +1) | | j = =0 | | j = = (cols +1)) {Data[i][j] =-1; }else {Data[i][j] =0;int Rowvar = i-1;int Colvar = J-1;while (Rowvar >0) {Data[i][j] + = (rowvar%10); Rowvar/=10; }while (Colvar >0) {Data[i][j] + = (colvar%10); Colvar/=10; }}}} Stackstack =New Stack (); boolean[][] Flag =New Boolean[rows +2][cols +2];for (int i =0; I < rows +1; i++) {for (Int J =0; J < cols +1; J + +) {Flag[i][j] =True } }Int[] init = {1,1}; flag[1][1] =FalseStack.push (init); result++;while (!Stack.isempty ()) {int[] Temp = (Int[])Stack.peek ();int row = temp[0];int col = temp[1];if (Data[row-1][col] <= threshold && Data[row-1][col] >0 && Flag[row-1][col] = =True) {Int[] Position = {row-1, col};Stack.push (position); flag[position[0]][position[1]] =False result++; }Elseif (Data[row][col +1] <= threshold && Data[row][col +1] >0 && Flag[row][col +1] = =True) {Int[] Position = {row, col +1};Stack.push (position); flag[position[0]][position[1]] =False result++; }Elseif (Data[row +1][col] <= threshold && Data[row +1][col] >0 && Flag[row +1][col] = =True) {Int[] Position = {row +1, col};Stack.push (position); flag[position[0]] [position[1]] = false; result++;} Else if (Data[row][col- 1] <= threshold && Data[row][col- 1] > 0 && flag[row][ Col- 1] = = true) { int[] position = {row, col- 1}; Stack.push (position); flag[position[0]][position[1]] = false; result++;} else { stack.pop ();}} return result;}}                  

Range of motion of the robot-sword