Create sort-array-by-parity.py

Python/sort-array-by-parity.py

@@ -0,0 +1,32 @@
+# Time:  O(n)
+# Space: O(1)
+
+# Given an array A of non-negative integers,
+# return an array consisting of all the even elements of A,
+# followed by all the odd elements of A.
+#
+# You may return any answer array that satisfies this condition.
+#
+# Example 1:
+#
+# Input: [3,1,2,4]
+# Output: [2,4,3,1]
+# The outputs [4,2,3,1], [2,4,1,3], and [4,2,1,3]
+# would also be accepted.
+#
+# Note:
+# - 1 <= A.length <= 5000
+# - 0 <= A[i] <= 5000
+
+class Solution(object):
+    def sortArrayByParity(self, A):
+        """
+        :type A: List[int]
+        :rtype: List[int]
+        """
+        i = 0
+        for j in xrange(len(A)):
+            if A[j] % 2 == 0:
+                A[i], A[j] = A[j], A[i]
+                i += 1
+        return A