save project

a.py

+a = 20
+num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
+l = 0
+
+while l <= h:
+    mid = (h + l) // 2
+    gue = num_list[mid]
+    if gue == a:
+        print("找到了，他的索引是", mid)
+        break
+    elif gue < a:
+        l = mid + 1
+    elif gue > a:
+        h = mid - 1
+    
\ No newline at end of file

my_search.py

@@ -6,4 +6,19 @@ for i in range(1, 101):
 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
 
-def binary_search(alist,num):
\ No newline at end of file
+def binary_search(alist,num):
+    l = 0
+    h = len(alist) - 1
+    while l <= h:
+        mid = (h + l) // 2
+        gue = alist[mid]
+        if gue == num:
+            return mid
+        elif gue < num:
+            l = mid + 1
+        elif gue > num:
+            h = mid - 1
+    return None
+result = binary_search(alist,num)
+print('老师给的数是',num)
+print('他的索引是',result)
\ No newline at end of file