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, 11, 15, 17, 18, 20, 21]
+
+def bsearch(l,num):
+    low=0
+    high=len(l)-1
+    while True:
+        mid=int((low+high)/2)
+        if l[mid]==num:
+            break
+        elif l[mid]>num:
+            high=mid-1
+        else:
+            low=mid+1
+    return mid
+
+print(bsearch(num_list,20))
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