auto save

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]
+num = 9
+low = 0
+high = len(num_list)-1
+
+while low<=high:
+    mid = (low+high)//2
+    guess = num_list[mid]
+    if num == guess:
+        print("找到了，索引值是：",mid)
+        break
+    elif guess < num:
+        low = mid + 1
+    else:
+        high = mid - 1
+if low>=high:
+    print('列表里没有对应的值')
\ No newline at end of file