save project

my_search.py

@@ -7,3 +7,16 @@ num = random.choice(alist)
 # 请完善二分查找函数binary_search(),查找出num在列表alist里面的索引位置
 # 请完善二分查找函数binary_search(),查找出num在列表alist里面的索引位置
 
 
 def binary_search(alist,num):
 def binary_search(alist,num):
+    print("目标数字是"+str(num))
+    minIndex = 0
+    maxIndex = len(alist)-1
+    while minIndex <= maxIndex:
+        mid = (minIndex + maxIndex)//2
+        if alist[mid] == num:
+            return mid
+        elif alist[mid] > num:
+            maxIndex = mid-1
+        else:
+            minIndex = mid+1
+        return None
+        print(binbry_search(alist , num))
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