diff --git a/Week03/pyramid_tarik_bozgan.py b/Week03/pyramid_tarik_bozgan.py
new file mode 100644
index 0000000..9bd324b
--- /dev/null
+++ b/Week03/pyramid_tarik_bozgan.py
@@ -0,0 +1,6 @@
+def calculate_pyramid_height(number_of_blocks):
+    height = 0
+    while number_of_blocks >= 0:
+        height += 1
+        number_of_blocks -= height
+    return height - 1
diff --git a/Week03/sequences_tarik_bozgan.py b/Week03/sequences_tarik_bozgan.py
new file mode 100644
index 0000000..1ba0206
--- /dev/null
+++ b/Week03/sequences_tarik_bozgan.py
@@ -0,0 +1,23 @@
+def remove_duplicates(seq):
+    result = []
+    for item in seq:
+        if item not in result:
+            result.append(item)
+    return result
+
+
+def list_counts(seq):
+    counts = {}
+    for item in seq:
+        if item in counts:
+            counts[item] += 1
+        else:
+            counts[item] = 1
+    return counts
+
+
+def reverse_dict(d):
+    reversed_dict = {}
+    for key, value in d.items():
+        reversed_dict[value] = key
+    return reversed_dict
\ No newline at end of file
diff --git a/Week04/arrays_tarik_bozgan.py b/Week04/arrays_tarik_bozgan.py
new file mode 100644
index 0000000..2d51c11
--- /dev/null
+++ b/Week04/arrays_tarik_bozgan.py
@@ -0,0 +1,20 @@
+import numpy as np
+
+def replace_center_with_minus_one(d, n, m):
+    if m > n:
+        raise ValueError("m cannot be greater than n")
+    if d <= 0:
+        raise ValueError("d must be greater than 0")
+    if n < 0:
+        raise ValueError("n must be greater than or equal to 0")
+    if m < 0:
+        raise ValueError("m must be greater than or equal to 0")
+    
+    arr = np.random.randint(10**(d-1), 10**d, size=(n, n))
+    
+    start_index = (n - m) // 2
+    end_index = start_index + m
+    
+    arr[start_index:end_index, start_index:end_index] = -1
+    
+    return arr
\ No newline at end of file