1 files changed, 39 insertions, 0 deletions
diff --git a/challenge-266/steven-wilson/python/ch-2.py b/challenge-266/steven-wilson/python/ch-2.py
new file mode 100644
index 0000000000..f6603f73a4
--- /dev/null
+++ b/challenge-266/steven-wilson/python/ch-2.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+
+
+def is_x_matrix(matrix):
+    ''' Given a square matrix, find if the given matrix is X Matrix.  A square
+    matrix is an X Matrix if all the elements on the main diagonal and
+    antidiagonal are non-zero and everything else are zero
+
+    >>> is_x_matrix([[1, 0, 0, 2], [0, 3, 4, 0], [0, 5, 6, 0], [7, 0, 0, 1],])
+    True
+    >>> is_x_matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9],])
+    False
+    >>> is_x_matrix([[1, 0, 2], [0, 3, 0], [4, 0, 5],])
+    True
+    '''
+    matrix_size = len(matrix)
+    diagonal_position = 0
+    for row in matrix:
+        antidiagonal_position = matrix_size - diagonal_position - 1
+        x = []
+        if diagonal_position < antidiagonal_position:
+            x.append(row.pop(antidiagonal_position))
+            x.append(row.pop(diagonal_position))
+        elif diagonal_position == antidiagonal_position:
+            x.append(row.pop(diagonal_position))
+        else:
+            x.append(row.pop(diagonal_position))
+            x.append(row.pop(antidiagonal_position))
+        if not all(elem != 0 for elem in x) or not all(elem == 0 for elem in row):
+            return False
+        diagonal_position += 1
+
+    return True
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod(verbose=True)