Added 2014/03/07 - Matrix Rotation

http://www.problemotd.com/problem/matrix-rotation/

20140307.py

@@ -0,0 +1,42 @@
+# Problem of the Day - 2014/03/07
+# http://www.problemotd.com/problem/matrix-rotation/
+#
+# By Andrew Williams
+ 
+from datetime import datetime
+ 
+start = [[1,2,3,4,5],
+    [6,7,8,9,10],
+    [11,12,13,14,15],
+    [16,17,18,19,20],
+    [21,22,23,24,25]]
+        
+target = [[21, 16, 11, 6, 1], 
+    [22, 17, 12, 7, 2],
+    [23, 18, 13, 8, 3],
+    [24, 19, 14, 9, 4],
+    [25, 20, 15, 10, 5]]
+        
+target_weekend = [[5, 10, 15, 20, 25],
+        [4, 9, 14, 19, 24],
+        [3, 8, 13, 18, 23],
+        [2, 7, 12, 17, 22],
+        [1, 6, 11, 16, 21]]
+        
+        
+def rotate_matrix(matrix, dow=datetime.now().weekday()):
+    if dow in [6, 7]:
+        return zip(*matrix)[::-1]
+    else:
+        return zip(*matrix[::-1])
+    
+def compare_matrix(matrix, target):
+    for i, a in enumerate(matrix):
+        for ii, b in enumerate(a):
+            if b != target[i][ii]:
+                return False
+    return True
+    
+if __name__ == '__main__':
+    print "Forward Check: {}".format(compare_matrix(rotate_matrix(start, 1), target))
+    print "Reverse Check: {}".format(compare_matrix(rotate_matrix(start, 6), target_weekend))