save project

my_search.py

@@ -6,4 +6,23 @@ for i in range(1, 101):
 num = random.choice(alist)
 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):
\ No newline at end of file
+    low=0
+    high=len(alist)-1
+    while high>=low:
+        mid = (low+high)//2
+        if alist[mid]==num:
+            return mid 
+        elif alist[mid]>num: 
+            high=mid-1
+        else:
+            low=mid-1
+    return "没找到"
+flag=binary_search(alist,num)
+print(str(num)+"的索引"+str(flag))
+
+
+
+
+
+