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
+
+
+c=11
 num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
 a=0
-b=0
-c=((a+b)//2)
-
+b=len(num_list)-1
+d=0
+e=0
+
+while a<=b:
+    d=(a+b)//2
+    e=num_list[d]
+    if e==c:
+        print("找到了，它在列表里的索引是：",d)
+        break
+    elif e<c:
+        a=d+1
+    elif e>c:
+        b=d-1