diff --git a/Week04/arrays_beytullah_arslan.py b/Week04/arrays_beytullah_arslan.py
new file mode 100644
index 0000000..2d258b6
--- /dev/null
+++ b/Week04/arrays_beytullah_arslan.py
@@ -0,0 +1,15 @@
+import numpy as np
+
+def replace_center_with_minus_one(d, n, m):
+    if m > n or d <= 0 or n < 0 or m < 0:
+        raise ValueError("Invalid parameters")
+    arr = np.random.randint(0, 10**d, (n, n))
+    if n == m:
+        arr[:] = -1
+    else:
+        start = (n - m) // 2
+        end = start + m
+        arr[start:end, start:end] = -1
+    return arr
+
+