9.29

Author: huangyt39

149.py

@@ -0,0 +1,15 @@
+class Solution:
+    """
+    @param prices: Given an integer array
+    @return: Maximum profit
+    """
+    def maxProfit(self, prices):
+        # write your code here
+        if len(prices) <= 1:
+          return 0
+        max_pro = 0
+        min_pri = 99999
+        for num in prices:
+          min_pri = min(min_pri, num)
+          max_pro = max(max_pro, num - min_pri)
+        return max_pro

411.py

@@ -0,0 +1,45 @@
+# 000
+# 001
+# 011
+# 010
+# 110
+# 111
+# 101
+# 100
+class Solution:
+    """
+    @param n: a number
+    @return: Gray code
+    """
+    def grayCode(self, n):
+        # write your code here
+      res = [[0,0],[0,1],[1,1],[1,0]]
+      res_ = []
+      if n == 0:
+        return [0]
+      if n == 1:
+        return [0, 1]
+      while(n > 2):
+        res_tmp = [arr[:] for arr in res]
+        res_tmp.reverse()
+        print(res)
+        print(res_tmp)
+        for arr in res:
+          arr.insert(0, 0)
+        print(res)
+        print(res_tmp)
+        for arr in res_tmp:
+          arr.insert(0, 1)
+          res.append(arr)
+        n -= 1
+        print(res)
+      for num_arr in res:
+        tmp = 1
+        num = 0
+        for index in num_arr[::-1]:
+          num += tmp*index
+          tmp *= 2
+        res_.append(num)
+      return res_
+
+print(Solution.grayCode(2, 4))

46.py

@@ -0,0 +1,27 @@
+class Solution:
+    """
+    @param: nums: a list of integers
+    @return: find a  majority number
+    """
+    def majorityNumber(self, nums):
+        # write your code here
+        max_res = 1
+        count = 1
+        nums.sort()
+        res = nums[0]
+        tmp = nums[0]
+        for index in range(1, len(nums)):
+          if nums[index] == tmp:
+            count += 1
+          else:
+            if max_res < count:
+              max_res = count
+              res = tmp
+            tmp = nums[index]
+            count = 1
+        if max_res < count:
+          return tmp
+        return res
+
+A = [1,1,1,1,2,2,2]
+print(Solution.majorityNumber(A, A))