save project

binary_search.py

 # 使用二分查找法，找出9和20在列表里面的索引
 # 使用二分查找法，找出9和20在列表里面的索引
-num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
+num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
\ No newline at end of file
+l = 0
+r = len(num_list)-1
+a = 9
+while l <= r:
+    m = (l+r)//2
+    if num_list[m] == a:
+        print(m)
+        exit()
+    elif num_list[m] < a:
+        l = m+1
+    elif num_list[m] > a:
+        r = m-1
+print("没找到")
\ No newline at end of file