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]
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+num_list = [1, 3, 5, 8, 9, 11, 15, 17, 18, 20, 21]
+num1=9
+num2=20
+low=0
+high=len(num_list)-1
+mid=0
+while True:
+    if low<=high:
+        mid=(high-low)//2
+        guess=num_list[mid]
+        if guess==num1:
+            print("9在列表中的索引是"+str(mid))
+            break
+        elif guess<num1:
+            low=mid+1
+        else:
+            high=mid-1
+    else:
+        print("没有这个数")
+        break
+while True:
+    if low<=high:
+        mid=(high-low)//2
+        guess=num_list[mid]
+        if guess==num1:
+            print("20在列表中的索引是"+str(mid))
+            break
+        elif guess<num1:
+            low=mid+1
+        else:
+            high=mid-1
+    else:
+        print("没有这个数")
+        break 
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