add dfs

Author: ss892714028

gifs/dfs.gif

@@ -0,0 +1 @@
+def a_star():

src/a_star.py

@@ -43,6 +43,7 @@ def bfs(win, startEnd, walls):
 
                 win.write('*', start_x + row[k], start_y + col[k], fgcolor='green')
                 q.append((start_x + row[k], start_y + col[k], dist + 1, add + move[k]))
+
     win.write('@', end_x, end_y)
 
     if min_dist != sys.maxsize:

src/bfs.py

@@ -1,7 +1,7 @@
 config = {
     "board": {
         'w': 50,
-        'h': 40
+        'h': 50
     },
-    "algo": 'bfs'
+    "algo": 'dfs'
 }

src/config.py

@@ -3,15 +3,69 @@
 from config import config
 from collections import deque
 import time
+import pygame
+
+
+def is_valid(mat, visited, row, col):
+    M, N = mat.shape
+    return (row >= 0) and (row < M) and (col >= 0) and (col < N) \
+        and mat[row][col] == 0 and not visited[row][col]
 
 
 def dfs(win, startEnd, walls):
+    clock = pygame.time.Clock()
     start, end = startEnd
     start_x, start_y = start
     end_x, end_y = end
     mat = np.zeros([config['board']['w'], config['board']['h']])
     for i in walls:
         mat[i] = 1
     M, N = mat.shape
-    
 
+    # explore 4 neighbors
+    row = [-1, 0, 0, 1]
+    col = [0, -1, 1, 0]
+    move = ['L', 'U', 'D', 'R']
+    q = deque()
+
+    visited = [[False for _ in range(N)] for __ in range(M)]
+    visited[start_x][start_y] = True
+    add = ""
+    q.append((start_x, start_y, 0, add))
+    min_dist = sys.maxsize
+
+    while q:
+        (start_x, start_y, dist, add) = q[-1]
+        if start_x == end_x and start_y == end_y:
+            min_dist = dist
+            break
+        found = False
+        for k in range(4):
+            if is_valid(mat, visited, start_x + row[k], start_y + col[k]):
+                visited[start_x + row[k]][start_y + col[k]] = True
+
+                win.write('*', start_x + row[k], start_y + col[k], fgcolor='green')
+                pygame.time.wait(3)
+                q.append((start_x + row[k], start_y + col[k], dist + 1, add + move[k]))
+                found = True
+                break
+        if not found:
+            q.pop()
+    win.write('@', end_x, end_y)
+
+    if min_dist != sys.maxsize:
+        # find path
+        start_x, start_y = startEnd[0]
+        for i in range(len(add)):
+            for event in pygame.event.get():
+                # Quit if the user closes the window.
+                if event.type == pygame.QUIT:
+                    return
+            index = move.index(add[i])
+            start_x, start_y = start_x + row[index], start_y + col[index]
+            win.write('+', start_x, start_y, fgcolor='red')
+            pygame.time.wait(5)
+        win.write('@', end_x, end_y)
+        win.write(f"The path from source to destination has length {min_dist}", 1, 1)
+    else:
+        win.write("Destination can't be reached from a given source", 1, 1)

src/dfs.py

@@ -7,7 +7,7 @@
 from collections import deque
 import time
 from bfs import bfs
-
+from dfs import dfs
 
 
 def drawer():
@@ -43,7 +43,8 @@ def drawer():
             elif event.type == pygame.KEYDOWN:
                 if config['algo'] == 'bfs':
                     bfs(win, startEnd, walls)
-
+                if config['algo'] == 'dfs':
+                    dfs(win, startEnd, walls)
 
 
 if __name__ == "__main__":