Adds android sudoku solver

Python/Android sudoku solver/README.md

@@ -0,0 +1,11 @@
+# sudoku-adb
+Python script to automate solving a sudoku game in android over ADB
+
+### See it in action 	[here](https://www.linkedin.com/posts/sonalagr_python-sudoku-automated-activity-6710469597004488704--Oji).
+
+## How does it work?
+- Extract the numbers into a 2D Matrix from the screenshot
+- Solve the incomplete grid using backtracking algoithm
+- Update the values by sending touch commands to device
+
+### Game download [link](https://play.google.com/store/apps/details?id=com.hagstrom.henrik.sudoku)

Python/Android sudoku solver/main.py

@@ -0,0 +1,77 @@
+# import required modules
+from ppadb.client import Client
+from PIL import Image
+import pytesseract
+import copy
+from sudoku import solve, print_board
+
+# connect to local adb server
+adb = Client()
+devices = adb.devices()
+if len(devices) == 0:
+	print("No devices attached")
+	quit()
+device = devices[0]
+
+# save a screenshot & load it using PIL
+result = device.screencap()
+with open("screen.png", "wb") as fp:
+    fp.write(result)
+im = Image.open("screen.png")
+
+# starting position of the grid on screen
+x, y = 3, 285
+
+# width & height of single cell
+dx, dy = 112, 114
+
+# grid contains the incomplete sudoku (9x9 matrix)
+# touch is also a 9x9 matrix where each element is a tuple containing pixel coordinate
+grid, touch = [], []
+
+for j in range(1,10):
+	grid_row, t_row = [], []
+	xcopy = x
+
+	for i in range(1,10):
+		# crop & zoom into individual cells
+		imcrop = im.crop((x,y,x+dx,y+dy)).crop((16,13,98,104))
+
+		t_row.append( ((2*x+dx)//2, (2*y+dy)//2) )
+
+		# every third vertical line is thicker
+		x += 11 if i%3==0 else 7
+
+		# extract the number from a cell
+		temp = pytesseract.image_to_string(imcrop, config='--psm 10')
+		temp = int(temp[0]) if temp[0].isnumeric() else 0
+
+		grid_row.append(temp)
+		x += dx
+	x = xcopy
+
+	# every third horizontal divider is thicker
+	y += dy + (12 if j%3==0 else 8)
+
+	grid.append(grid_row)
+	touch.append(t_row)
+
+# solve & print the board
+orig_grid = copy.deepcopy(grid)
+solve(grid)
+print_board(grid)
+
+def click(i, j):
+	device.shell(f'input touchscreen tap {touch[i][j][0]} {touch[i][j][1]}')
+
+def select(n):
+	arr = [123, 212, 314, 410, 515, 623, 724, 839, 937]
+	device.shell(f'input touchscreen tap {arr[n-1]} 1453')
+
+# update values on screen
+for i in range(len(grid)):
+	for j in range(len(grid[0])):
+		# only click on cells that were empty initially
+		if (orig_grid[i][j] == 0):
+			select(grid[i][j])
+			click(i, j)

Python/Android sudoku solver/sudoku.py

@@ -0,0 +1,85 @@
+# copied from https://techwithtim.net/tutorials/python-programming/sudoku-solver-backtracking/
+
+# board = [
+#     [7,8,0,4,0,0,1,2,0],
+#     [6,0,0,0,7,5,0,0,9],
+#     [0,0,0,6,0,1,0,7,8],
+#     [0,0,7,0,4,0,2,6,0],
+#     [0,0,1,0,5,0,9,3,0],
+#     [9,0,4,0,6,0,0,0,5],
+#     [0,7,0,3,0,0,0,1,2],
+#     [1,2,0,0,0,7,4,0,0],
+#     [0,4,9,2,0,6,0,0,7]
+# 
+
+# board = [[6, 0, 0, 0, 9, 0, 0, 1, 0], [3, 9, 0, 5, 0, 2, 0, 0, 0], [0, 0, 2, 0, 0, 0, 0, 0, 4], [0, 0, 0, 9, 0, 5, 0, 2, 0], [0, 4, 0, 0, 2, 0, 7, 0, 3], [0, 0, 6, 0, 8, 0, 9, 4, 0], [0, 3, 0, 4, 0, 1, 0, 6, 7], [0, 5, 0, 0, 0, 0, 8, 0, 9], [0, 0, 7, 0, 0, 9, 4, 0, 1]]
+
+def solve(bo):
+    find = find_empty(bo)
+    if not find:
+        return True
+    else:
+        row, col = find
+
+    for i in range(1,10):
+        if valid(bo, i, (row, col)):
+            bo[row][col] = i
+
+            if solve(bo):
+                return True
+
+            bo[row][col] = 0
+
+    return False
+
+
+def valid(bo, num, pos):
+    # Check row
+    for i in range(len(bo[0])):
+        if bo[pos[0]][i] == num and pos[1] != i:
+            return False
+
+    # Check column
+    for i in range(len(bo)):
+        if bo[i][pos[1]] == num and pos[0] != i:
+            return False
+
+    # Check box
+    box_x = pos[1] // 3
+    box_y = pos[0] // 3
+
+    for i in range(box_y*3, box_y*3 + 3):
+        for j in range(box_x * 3, box_x*3 + 3):
+            if bo[i][j] == num and (i,j) != pos:
+                return False
+
+    return True
+
+
+def print_board(bo):
+    for i in range(len(bo)):
+        if i % 3 == 0 and i != 0:
+            print("- - - - - - - - - - - - - ")
+
+        for j in range(len(bo[0])):
+            if j % 3 == 0 and j != 0:
+                print(" | ", end="")
+
+            if j == 8:
+                print(bo[i][j])
+            else:
+                print(str(bo[i][j]) + " ", end="")
+
+
+def find_empty(bo):
+    for i in range(len(bo)):
+        for j in range(len(bo[0])):
+            if bo[i][j] == 0:
+                return (i, j)  # row, col
+
+    return None
+
+# print_board(board)
+# solve(board)
+# print("___________________")
+# print_board(board)