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
 num_list = [1, 3, 5, 8, 11, 15, 17, 18, 20, 21]
-
-
+num=20
+low=0
+high=len(num_list)-1
+while high>low:
+    mid=(low+high)//2
+    g=num_list[mid]
+    if g==num:
+        print(mid)
+        break
+    elif g<num:
+        low=mid+1
+    else:
+        high=mid-1