From 99d13082ee2714d110a730b4c63dbd4cb068610a Mon Sep 17 00:00:00 2001
From: Shubham Padkonde <shubhampadkonde12@gmail.com>
Date: Fri, 23 Oct 2026 21:48:29 +0530
Subject: [PATCH] Reject blocked endpoints in binary-grid Dijkstra

---
 graphs/dijkstra_binary_grid.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/graphs/dijkstra_binary_grid.py b/graphs/dijkstra_binary_grid.py
index 06293a87da2d..736623a4cc2a 100644
--- a/graphs/dijkstra_binary_grid.py
+++ b/graphs/dijkstra_binary_grid.py
@@ -44,6 +44,9 @@ def dijkstra(
     (4.0, [(0, 0), (0, 1), (0, 2), (1, 2), (2, 2)])
     """
     rows, cols = grid.shape
+    if grid[source] != 1 or grid[destination] != 1:
+        return np.inf, []
+
     dx = [-1, 1, 0, 0]
     dy = [0, 0, -1, 1]
     if allow_diagonal: