leetcode 4

4. Median of Two Sorted Arrays/code.py

@@ -1,23 +1,73 @@
 from typing import List
+import math
 
 
 class Solution:
 
     def findMedianSortedArrays(self, nums1: List[int], nums2: List[int]) -> float:
         m_index = []
+        m_val = []
         l_1, l_2 = len(nums1), len(nums2)
-        aver_len = l_1 + l_2 // 2
-        if aver_len == 0:
-            m_index.extend([aver_len-1, aver_len])
+        aver_len = (l_1 + l_2) // 2
+        if (l_1 + l_2) % 2 == 0:
+            m_index.extend([aver_len-2, aver_len-1])
         else:
             m_index.append(aver_len)
+        # print("中位数在整体数组中的索引位置：", m_index)
+        p_l1, p_l2, cur = 0, 0, 0
 
+        while p_l1 < l_1 and p_l2 < l_2:
+            if nums1[p_l1] < nums2[p_l2]:
+                p_l1 += 1
+            else:
+                p_l2 += 1
+            cur += 1
+            if cur > int(math.fsum(m_index)):
+                break
+        # print('cur:', cur, '\np_l1:', p_l1, '\np_l2:', p_l2)
+        if cur <= int(math.fsum(m_index)):  # 说明两个数组，至少有一个数组已经扫描结束
+            if p_l2 == l_2:
+                p_l2 = p_l2 - 1
+                temp = nums2[p_l2]
+                arr = nums1
+                p = int(math.fsum(m_index)) - p_l2
+            else:
+                p_l1 = p_l1 - 1
+                temp = nums1[p_l1]
+                arr = nums2
+                p = int(math.fsum(m_index)) - p_l1
+
+            flag, ind = 0, 0
+            print(m_index)
+            print(p)
+            for i in range(len(m_index)):
+                if (flag == 0) and min(arr[p + ind], temp) == temp:
+                    flag = 1
+                    m_val.append(temp)
+                else:
+                    m_val.append(arr[p + ind])
+                    ind += 1
+        else:
+            #  说明中位数在两个指针前部，两个数组的指针都没有扫描结束
+            if p_l1 == l_1:
+                p_l1 = l_1 - 1
+            else:
+                p_l2 = l_2 - 1
+            m_val.append(min(nums1[p_l1], nums2[p_l2]))
+            if len(m_index) > 1:
+                m_val.append(max(nums1[p_l1], nums2[p_l2]))
+
+        return math.fsum(m_val) / len(m_val)
 
 
 if __name__ == '__main__':
     solution = Solution()
-    nums1 = [1, 2]
+    nums1 = [1, 2, 7, 9]
     nums2 = [3, 4]
+    # nums1 = [1, 3]
+    # nums2 = [2]
+    # nums1 = []
+    # nums2 = [1]
 
     print((solution.findMedianSortedArrays(nums1, nums2)))
 

4. Median of Two Sorted Arrays/code1.py

@@ -0,0 +1,22 @@
+from typing import List
+import math
+
+
+class Solution:
+
+    def findMedianSortedArrays(self, nums1: List[int], nums2: List[int]) -> float:
+
+        return
+
+
+if __name__ == '__main__':
+    solution = Solution()
+    nums1 = [1, 2, 7, 9]
+    nums2 = [3, 4]
+    # nums1 = [1, 3]
+    # nums2 = [2]
+    # nums1 = []
+    # nums2 = [1]
+
+    print((solution.findMedianSortedArrays(nums1, nums2)))
+